Yes, replacing the present electric solenoid valve with a direct vacuum lock off is practical.
If the electric solenoid valve on there now is activated by a vacuum or oil pressure sensing switch, it is legal and as practical as a direct vacuum lock off.
I just wanted to caution against simply wiring in a solenoid valve to a circuit that is hot with the key on.........as that does not satisfy the requirement that fuel flow be automatically interrupted if the engine dies while the key is on.