I inherited a like new 659 from my step father with one flaw. It's missing the back strap. Does anybody know where I can get a back strap for this gun? I've done some searching and only found the Pachmyer Grips with backstrap, but I believe they only cover the original not replace it. Since the back strap on the 659 holds the mainspring that won't help me. Any info would be very much appreciated.

You might call S&W.

Try Numrich. It looks likes like they have the backstrap for the 459.
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Worst case the color maybe black instead of SS.

They are sold out of the one listed for the 659. Will the one you linked to for the 459 work? If so I'll order it. Shouldn't look to bad since the grips are black.

Mechanically the 659 & 459 are the same gun. Just a difference of finish coloring stainless vs. Black. It appears the 659 had a metal or grey plastic backstrap. And the 459 black. Which surprisesme because I have a 669 (compact) and it has a black plastic backstrap and it looks fine

Thanks for the info. Got one ordered & on the way.

The quick response is much appreciated.