Dang, but I wish someone would come up with a 7.62x25mm bolt gun.  Maybe something the size of a Destroyer Carbine, er something like that.
Failing that, one could always go the route of those chamber inserts - get a half dozen for a 30 caliber bore and shoot the 7.62x25 through those.  Problem would be accuracy though - an awful lot of free travel before the bullet connects with the rifling.  
7.62x39mm bores are too large, as the bullets for the pistol round are .308 diameter.  Rebarrel something  in a 32-20 caliber, or maybe a 32 Mag - but most of those are levers.  Any ideas fellas?????  Mikey.