Your best bet for getting measurements is to ask on the MTFCA forum, which is very active and has lots of participants. Somebody there is likely to have 1927 doors they can measure for you.
47-3/4" high by 29" wide at the latch side, and 47" high on the hinge side on my '26 coupe.
Coupe and 2-dr Sedan had the same size doors and are fairly easy to find.
Good luck.