Cows Knees and Lock Covers

[caintuckrifle]

Has anyone been able to find any historical reference for the use of lock covers of any sort in use among the mountaineers? I would like to make a cover from some hair on buffalo hide for my Lancaster, but I would like to find some references first. I am thinking that the most common would have simply been a piece of hide or wool wrapped around the lock area and perhaps tied. If you have any references, opinions, or things that work for you please share.
Thanks, Caintuck