I was the runner up bidder in that auction - congrats, I think you picked up a good set.

I have no doubt they are Sandersons. With Sandersons you are looking for a certain look and feel as far as being able to identify / authenticate them, and that set conforms. I have a set very similar on a K22. That Colt pin hole - I'm sure the seller is correct about that - thats where the pin hole is for the Offcers Models, Pythons, and OPs.