Apologies if this is an often discussed topic but I've had a look around and the consensus seems to be that the Lyman 311359 mold is the best one for accuracy out of the M1. As far as I can tell thought the 311359 has been discontinued? I don't know if that's the case or if it's just out of stock everywhere.
Assuming that the Lyman one can't be found are there any other good suggestions people have? I was intending to gas check and powder coat.