A couple of the Thai makers offer to sell the stocks with or without medallions. Which means that they can install the medallions,, one or two as you like.
The medallions themselves are sold on EBay and other places...
Lot of 2 Smith & Wesson S&W Original Grip Medallion & Washer NEW OLD STOCK! | eBay
Numrich occasionally has S&W medallions.
There are other options as well.
Tombstone Gun Grips: Medallions
SMITH WESSON SILVER Grip Medallions FACTORY OEM pistol revolver Gun PART ( RARE) - $19.77 | PicClick
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