I just had my shot out Bolo relined to 7.63 Mauser (I can get Fiocchi stuff all day long though at $33 a box of 50 but I also reload). Redman's Rifling and Reboring did mine and I thought he did pretty darn good work (taking my Bolo out this weekend to give her a field test). He only does the resleeving now and no 9mm conversions. I had heard there was another outfit in Florida which does both (Broom Closet?). No contact info for them, though, as Redman is 'local' (in Washington State) and so I thought I'd send it to him since he's only a few hours drive away.
http://www.redmansrifling.com/mauser.htm
He does have a wait time but I sent it it to him in October, he told me (in writing) that he received it and it might be up to 5 months. Well, the barrel extension and bolt showed up last weekend a bit early (though no guarantee that it will happen early for anyone else). For me, it was very hard to see the seam line from the muzzle so I thought he delivered in spades! Very pleased with Mr. Redman's work.
As for the bolt stop; I have bought new ones from KB Tactical Star along with replacement springs. The bolt stops are new production and they seem to have a good supply of other parts, too.
http://www.kbtacticalstar.com/index....roducts_id=133
Hope that helps a little. Nice looking pistol, by the way! I have an M1930 as well which is also shot out but not sure yet I'll send that one in, too. Mine keyholes at 7 yards but not every shot and only with actual 7.63 bullets. It seems to keyhole far far less with .311 and .312 diameter bullets.