you might want to consider looking on the MUL for the "C" refits.. these are inner sphere mechs refitted to clan spec weaponry, generally for use in garrison forces. they are a fairly mixed lot (some of them are really good, some are downright terrible) but several of the plastics have "C" refits available.
also, many of the wolfs dragoons designs (shogun, annihilator, Hoplite, etc) have clantech versions as well. either because they were originally designs the clans developed, then downgraded for the dragoons, or were dragoons inventions they later upgraded to clantech.