I do not believe there is such a thing. There are a number of names of smiths some members have used. But I must say, its not a hard task, easier than other action types.
I would talk to local gun shops see who they use. This kind of rechamber is basic rechambering for a gun smith, not overly difficult or expensive.
Heck, some of the members here do most of there own!
Good luck,' CW
EDIT: Where are my manors... WELCOME LIL' JOE!!