You looking for wood or synthetic?
I've been actively looking for a wood bantam stock and they are next to impossible to find at the moment. Brownells has an unfinished bantam blank with no hardware that will require fitting. If you have synthetic in mind that one's easy. Hogue offers their overmolded stock in a 12" LOP, same length as the factory bantam wood stock. I have two of the Hogue 12" LOP stocks and they're great...
I have on on a Rem 870 and it's very nice. Wonder how it would work out on the 930?
Totally different animals there.
The 930 stock houses a buffer tube and spring...