TweetTry your local gun shops. They should throw some catalogs on the counter, dig to the section you need, and tell you to pick out which one you want ordered. They might even have some in stock that you'd like.
That's a damn fine gesture and gift as well. I'm sure that's one that would make your father proud.
You just need the brand, model, and serial number wouldn't hurt. Unless you have the gun. Then you're all set. It's a quick change too.
Goo Luck! I hope you find what you're looking for.