Very nice, congrats on your find. I have been looking for a 64 snub for a while now with no luck. The 64’s are some of the best K frames smith ever made. They are the perfect balance of simplicity, durability, and size.
I say go for it. The HB model 64’s/10’s are one of my favorite K frame’s and are crazy accurate. That price is a good deal imo. They are only going to increase in value. It being a -1 I would say it was produced sometime in the mid 70’s. Here is my model 64-1.
The M640 would be my first choice followed by a centennial airweight. Sounds like your friend needs to try a wheelgun as he doesn’t know what he’s missing. Revolvers remain a very viable option in today’s times..
If you are looking for an M66 for carry, any prelock M66 will serve you well. I would also consider a M65 with a 3 inch barrel. IMO it is one of the best carry revolver’s S&W ever created.