Some grip sellers at large gun shows have 1950's-'60's stocks at reasonable prices. You could get those and add a grip adaptor.

I'd see if the older, two-panel Pachmayr grips will fit and use those.

Why buy this old gun? Even heat-treated, the gun isn't meant to fire Plus P loads, and I prefer those for defense or shooting animals the size of a raccoon or coyote.

You could use Buffalo Bore's full (850 FPS) full wadcutter loads and have a pretty lethal round that isn't at Plus P pressure.

I'd only buy the gun for nostalgia reasons, to have an older M&P, a classic S&W revolver.

If you want a reel world, frequent use gun, put the money into a Model 64. Same basic idea, but modern metallurgy and stainless steel.