Again, it depends on the level of execution. Collectors of high end pipes, whether rare antique pieces, or top end Danish artisanal pipes, who need something like a stem replacement or some sort of structural, as well as aesthetic restoration, go to George Dibos. They line up to have George do the work because they want it faultless, seamless, and invisible. He's a member here.
If your repairs are more along the line of refurbishment, a clean up, a bit of spit and polish, the other recommendations are more than adequate