Looking at it again, I see another way. Do you have a big bench vise and a BFH? Why not fabricate a strap of 1/8" steel, maybe an inch wide, and bolt one end to that oil pan bolt, or the block drain bolt, and the other to the oil filter adapter bolt? Work the metal and have it bend over to the broken part with a hole in it so you can have a nut/washer on one side and the bolt on the other? I can be as shadetree as they come but it beats changing blocks.
