Holster: Sidearmor.
The best holster for a 625: rugged, strong, durable. Retention works very well, no thumb-snap to break, no leather to rot, crack or peel.
Very easy to re-holster your revolver while keeping focused on potential threat, etc. Not cheap, $80.95 retail, but the best holster I have ever owned for any working revolver.
BTW, I don't advise letting some smith or whoever start swapping out parts; just shoot it a whole bunch, and it will smooth out just fine.