Cimarron has a custom service that can give a pistol that peuter look and have the appearance of a 130 year old smoke wagon at a very reasonable price. They can also very tastefully slightly age the grips to match.
If stags are to your liking you can pick up a set of jigged bone grips like the ones Roy Rogers and Gene Autrey used and they're not expensive and look authentic.
Real stags are more costly, but let them soak for just a little while in a pot of water with tea bags and you'll have a pair that looks naturally aged. Soak'um too long and the'll soften up and warp. John Wayne used that trick on his fake ivories. Many wonderful things can be done to that gun. It just takes a little imagination and a few bucks.