Once, I bought a completely rebuilt OMC outdrive for 800$, for a ski boat. Don't remember his name but it was rebuilt by a guy from Coos Bay Oregon who was known for impeccable work... he was completely blind.agreed. motor side parts are NLA. the drive side parts are also becoming NLA
with it sitting a long time, the rubber impeller is in need of replacement
the transom boot will need replacement
the drive should be serviced. the ball gears will most likely need to be replaced.
being a 55 year old boat, check for rot