I once had an opportunity to handle and carefully examine the first 20 gauge DeLuxe Grade Smith gun ever built, and that elaborately embellished gun with its beautifully carved stock was fitted with Hunter's standard hard rubber butt plate; so perhaps we shouldn't consider this butt-plate as plain, but rather as an LC Smith "trademarked" feature. But to answer your question, if money is not an issue in your restoration; I would opt for a very nice leather covered pad. Leather pads done right are a great custom touch to a high-grade double gun; but I would be very discriminating in my choice, as I have seen many leather pads that did not compliment the finished gun. If I didn't want to spend the bucks for a good leather pad and planned to shoot the gun, I would opt for a period Silver's Pad; but insist that the heel spur be left on the pad and properly inletted, as a properly inletted heel spur is a very nice aesthetic touch to a rubber pad on a high grade gun. If I did not plan to shoot the gun, I'd probably just install the aforementioned plain, hard-rubber butt plate. Good luck, when you get that restoration completed; post some pics, as I'm sure members would enjoy seeing them.