Old magazines and books some help for identifying mystery holsters and grips, but often add to the mysteries.
Askins recommends grips by Kenneth Strine in his prewar book and has a picture of Strine - but not an identified picture of his grips. A couple of grips pictured have two screws instead of the usual one - but are those by Strine. I mention that specifically because several pictures of grips with double screws have been posted here over the years. They might be Strine, but maybe not.
In this case, the smooth grips in the Roper/Skelton style look rather like the grips in this 1959 ad for "Combat Grips" Custom Craft, Pasadena, California. A maybe.
(Not to be confused with the "Custom Wood" brand Farrant copies in the 1970's.)
The metal disk shows up in what I think of as inexpensive grips (often Italian) from the 60's, but it seems a very sensible method of making that arch.
I'll borrow pictures of Linde's mystery checkered Fitz marked grips that have the asymmetrical palm swell and the metal disk.
Notice to grip makers: mark your grips!!