63 max wedge?
If your friends block started as an Industrial or Marine engine, it should have the AAQA mark cast into the right front face of the block. That would make it worth a couple of bucks to someone looking to restore or accurately clone a Max Wedge. Also, the 413 goes out to 426 with just a .070 cut. There are many piston choices at that size. I'd say you could have an interesting builder there if the price is right.