To give you a comparison, I bought a 4bolt main 350 short block for $50.00 from a junk yard. Didn't have to pull it, just load it up. It's been in my pickup 4x4 for about 50,000 miles now. I don't think I would go to all that trouble for a 307. Nobody wanted them back then and I doubt if anyone is standing in line for them now. It just seems like to much effort and expense for that engine.