Look for Vintage Mershon Imperial grips
As my title says, I think what you are looking for is the old Mershon Imperial Grip.
Mershon Company of Los Angeles California sued Frank A. Pachmayr for trademark infringement and unfair competition in 1954 or so, lost and appealed in March 1955, lost again and then Pachmayr (dba Pachmayr Gun Works) acquired Mershon and the name was gone forever.
The pictures attached show the Mershon on my Model 65, and I tell you for fact...tight fitting, very comfortable, tames the full house maggies, much better accuracy (for me) than the original service stocks.
The info molded inside the both panels is " S & W K - Small" and when the 2 panels are assembled tight the butt mold information shows " US Pat. No. 3,678,084 Imperial Grip" on right panel, " by Mershon Company Los Angeles Calif. Made in USA" on left panel. The special screw does not protrude the opposite side.
Mine came to me on a 38 WWII Victory, and I have spent several years hunting down the correct smooth walnut service stocks along with a lanyard loop, swivel and pin but have really been pleasantly surprised at the comfort, control and use of these Mershon on the Model 65.