sassyrose,
In 2005 I toured the Clark Parts Distribution facility in Louisville, KY & they had an old truck loader on display in the lobby. The Clark folks "claimed' they still could get parts for it - may have been some marketing BS.
But if you have a serial number you might want to contact a Clark dealer, if you have a long time Clark dealer in you area the would be a plus or contact Clark direct - website clarkmhc dot com > just replace the dot with a. & eliminate spaces. w/o a complete s/n you will be SOL. Look for a stamping in the frame somewhere or on the data plate.