I have a very sound pair of diamond magna grips which I always figured were for a K frame. Today I put them on my old 1949 vintage K38 and found that the length was correct but they were too small along the backstrap. I don't have a J frame to try them on. Are these J frame grips?
Julian - can you take a picture of them on your K38?
If they are proper length and they are sq butt, they could be Spanish copies.
Do they have medallions? Are they rd or sq butt?