How to choose a used engine??

Any old engine in the junk yard that has not been run in who knows how many years should be treated as a core for rebuilding. That being the case and my experience a 318 should cost you about $100 and a 360 $150. If you want to make a road trip to the Boston area I have a 318 and 904 you can have.

A stock cast iron manifold whether it's a 4bbl or not should not cost any more than $25 at the junk yard. A new Edelbrock Performer is around $200 and the Performer RPM is $220. You can get them from any number of places like Jegs, Summit, Mancini for that price. A used one at a swap meet will run $50-$100. I picked up a Professional Products CrossWind new on EBay for $140.