I remember Tom. He used to have the same type table setup of parts and DR guns at the OGCA Shows.
I bought quite a lot of parts from him for making up rifles on shotgun actions.

I still have one set of 30cal bbls and the top and bottom rib for them.
Never got around (yet!) to making anything with them. I think a 30-30WCF was my idea at the time on a 20ga German SxS.
Maybe a 32-20 on a .410 SxS. .308 bore 32-20 is a fairly popular cartridge and takes nothing special to reload other than using a .308 expander in the die.

Anyway,,
IIRC he told me a lot of the bbls he had came from Italy.
He had rifled Shotgun gauge bbls as well. I did a 12ga on a Parker with a set of those.
Interesting guy and he always had something I seemed to need.
I think I have a catalog from him around as well. Just a price list really.