Those unmarked heads appear to be unmarked OFFENHAUSER style. Here's some info:
https://www.jalopyjournal.com/forum/...heads.1179803/
The stamping shown on the block shown was frequently done as part of a date code. HERE'S SOME DATE CODE INFO.
https://www.fordbarn.com/forum/showt...LOCK+DATE+CODE
I don't think Mark Kirby made any 8BA style heads but, if he did you can be sure they would have had the MCF logo.