Unless I'm mistaken (again) the melting point of silver is hotter than the melting point of copper.
Tinning copper is not difficult. A large hardware store should have either pure tin bars or a lead free solder consisting of about 94-96 % tin and 4-6% silver. You can heat the vessel to be tinned with a propane torch, then simply apply the tin, spreading it with a clean cotton pad held in a pair of pliers.
I have a HBCo replica 1 qt kettle that leaked when I got it and was quite rough inside. I retinned it that way, smoothing the inside as well as stopping the leak.
Three Hawks