Plating has been found as a factory option on LC Smith shotguns. I found a Number 3E that looks to be plated. In fact I looked at it again the other day and think that it is plated. The Sousa LC was Silver plated if I recall correctly. I think you will find that anything a person wanted and was willing to pay for was available from the builders of the LC Smith shotguns.

Regards
M.L.