Comment FreeDOS? (Score 2) 57
If Microsoft Open Sources 6.22, it would be best since we don't have access to PC DOS source code either despite having an unlimited license agreement with IBM for PC DOS 2000.
As you seems you need something more modern and with source available:
Have you given FreeDOS a try?
I my limited tests (retrogaming) it seems pretty stable and useful, though your embed use case might have different requirement (complex network stack or dedicated hardware interface on ISA cards that has only been validated against a couple of commercial DOS versions)