351W? HOW MUCH $$$$

Personally, I think $500 is too much. From what I see in my area, you can buy engines every day from 289s to 460s anywhere from $150 to $350. I guess it depends on where you live and how many are out there for sale. I think a fair price for what you are looking at with no intake and fuel delivery, I wouldn't pay over $300. That's just me.