almost every single one I've ever seen had a 366 in it. I know that the small block 350 was offered but have seen very few. Lots of 292s and 366s. I would imagine you could look up a C10,20,30 with a 350 timing chain and that parts would be identical, also see if C60 shows up with an option they seemed to be more popular than the 50's. Maybe that route might turn up some more results. Its hit of miss on the medium duty trucks finding parts. Got to be creative.
