believe it or not you may want to price your items from the OEM as well as local places. I ran into something similar the other day. I priced seals online as well as locally for the steering gear. I found them through a forklift dealer far cheaper (1/3) than I could get them anywhere else. it pays to shop around. BTW material handling resources http://www.mhrweb.com/ has had the best prices on EVERYTHING I have been looking for. everything from seats to bearings to carriages.

Also beware of e-bay auto parts lots! they can be seconds or thirds or downright factory rejects! and never buy electrical parts off e-bay. Chances are youll end up with fried parts that were repackaged, youll never know until you install them and find out they don't work.

Juanhanded: Just because a part is made by the same manufacturer means the parts are the same quality. In you pulley example the bearing is the most critical part. Most bearing manufactuers are capabable of producing bearing of varying quality (life expectancy) by changing the material make up of the bearing or producing a bearing to closer tolerance levels - like a Good, Better, Best. How could you determine that by looking at them. I worked for a lift truck company that built their own motor controller that used power transistors that were relatively expensive. They saught a new supplier that offered one at a lower price (but at a wider tolerance operating range). The results were catastrophic. Remember you get what you pay for. Also it is not uncommon to get different selling prices for the the same part at differnt dealers (auto & forklift). In the forlift business it is common that dealers will sell parts above the manufacturer's suggest list price.

duodeluxe, i took it for granted that part of the process of crossing over the oil filter at an auto parts store would include a comparison of the price.
all aftermarket parts have potential quality pitfalls, no matter where they are procured. By the same token, genuine OEM parts present pitfalls in pricing, and only an experienced hand can tell the difference between parts priced due to quality and complexity, and parts priced to cover warehousing/shipping/brokerage costs. the only way to avoid these pitfalls is with experience and technical knowledge, there is no magic formula that can be passed on to a novice. The only formula that works with any reliability is that purchasing genuine parts from the manufacturer as often as possible will ensure the fewest quality-related parts failures, and the most after sales support from the manufacturer.

If dealers(auto anyways)aren't your first choice for reasonable parts it's something dealers themselves have earned on their own.If you've been around a while,you get a sense for what is safe to get aftermarket and what item should be dealer only supplied. I couldn't find an idler pulley for my **** car aftermarket so I contacted my neighbor who is the Parts Manager at the dealer.I wanted 2 pulleys (if one is shot,the other can't be too far behind).He priced them at $175 each.I finally figured out that NAPA had them at $40 each.I unboxed them and they were identical pieces,by the same manufacturer.It's just a pulley with a bearing pressed in it,not a big bit of engineering.
That's just an example of why people don't run to the dealer first.When you get something that is in the reasonable range,it always seems surprising.Until you price out the next thing and get hit over the head.I mean I walked into a GM dealer to get some GM antifreeze for a van with a motor known to have cooling issues with it's system.Dealer rang them up at $45 a gallon.The girl on the other side of the Parts Dept is still waiting for me to pay for that one. I walked across the street and bought Prestone "GM approved" antifreeze for $15.Probably made and packaged in the same plant.
I don't buy junk parts.I stick to Blue Streak,Moog,Walker,etc. No junk no name chaiwanese stuff on any of my stuff.If the dealer is within 25% of the cost,I'll pay it no problem.But half the time you end up walking away clutching your chest.If the dealer was reliably reasonable,they would have a line out the door.
Sounds like lift truck dealers are totally different.BTW, I'm not shopping if a filter is $12.

duodeluxe-
Point well made. This also applies to automobile parts house vs OEM car dealers.
I USED to think people like Auto Zone, O'Reilly's, etc were less expensive on NEW parts than my local Ford dealer. By dumb luck I went to the Ford dealer because all the independents in my area did not have teh part instock & much to my surprise the Ford dealer had the parts & was less expensive.
Plus, I can be rest assurred the parts have the latest Engineering updates - dealers have to scrap the parts espically if the update is safety related. Don't get that warm fuzzy feeling with an independent. Been buying my Ford parts needs from my local dealer ever since, of course I compare prices to the independents. If Ford is 10-15% higher I go with then - I'll pay the extra for that for the warm fuzzy feeling.
Had a lift truck customer in the plywood making industry with a fleet of 65 - 7k box car specials, 5 years old - they complained that my truck were no good ,they were buying 25 hydraulic pumps (Tyrone gear type)/month at $250 each. On further investigation the customer was buying a hydraulic filter that was cheaper for about $7/filter but it was a 40 micron rated element. Our OEM filter was $25 but was 10 micron rated. We gave them enough filter to change out his fleet - hydraulic pump usage went down to less than 10/month. He started buying OEM filet after that.