Ive got a 350 block that came with my dads blazer. It was a rebuilt engine like what you would get at autozone or the like. Its bored over to were cylinder dia. is 4.050. (Thats if i micd it correctly) I have thought of a 383 but as of now i doubt i will have that kinda money once i start rebuilding this engine. The first thing i will have to do is take the block to the machine shop and get it cleaned, honed(hopefully it doesnt have scratches and scouring in the cylinders), get it magnafluxed, and check the line bore. If thats all that needs to be done i think it came out to be like $260ish.