Anthony - don't know where you are located but I believe 'Mentor Arms' (

) on Long Island in New York rebuilds and refurbishes the 96 Mauser pistols like yours.
If your 30 Mauser barrel is shot out, I believe they can either replace it in the same caliber, as current usable ammo is now available, or rebarrel/reline in 9mm or possibly even 9mm Export (similar to the 9mm Largo).
Keep checking the Shotgun News for their adds, I see them now and then.
BTW, if you send your pistol to them they will completely refurbish it with new springs and a complete checkover. I have seen a couple aof their pieces at some guns shows and they make me drool. HTH. Mikey.