Yep, that's a S&W revolver, customized by Volquartsen.
Back in the late 80's, Tom Volquartsen had a table set up at our local gun show.(They're in Carroll, IA. The show was in Des Moines.) I bought a .22 pistol from them, and with that pistol, I got a brochure that showed all of their models and options. On the back page was a description of all of the fine things they would do for you S&W revolver.