I have installed several grip frames from RW Gripframes. Ronnie makes CNC machined frames out of brass and aluminum to fit both NM and 3 Screw Rugers. There are both original style reproductions and custom designs available in brass and aluminum. He can supply rough fitted grip panels also.
They are not cheap but they are works of art. Aluminum is currently $300 and brass $350.
As far as fitting, there is minimal work required compared to Ruger replacement parts. I have never had to reblue or even touch up a frame- you sand down the excess and sneak up on a perfect match. I scribe a line on the new frame as a guide. Or, Ronnie will do it for you for $150 currently.
I can post pics of the fitting process if anyone's interested.
I just fit this one- Dealer model- to my .357. It's going out for E100 Cerakote soon.
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And a brass one on a Single Six.
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