Master cylinder for manual disc brakes?

I agree. You can't go wrong with a brand new aluminum one from Dr. Diff which includes a two bolt mounting adaptor. I got my 1.03" one from him.

I would stay away from a parts store reman aluminum unit for two reasons: a) Reman aluminum units were known to fail because they couldn't rebuild them and not leak and b) you're likely to receive an iron body these days anyway because of "a".