Opps! Totally missed your post, Fernando! Thanks for responding. I'm hoping the 'R' does stand for regiment, as that might help me track down the troop. I was quite surprised that the Jager corps had a great impact on many of the battles of the American Revolution. They came from multiple regions of the old Germanic empire and were exemplary in helping their British allies turn many of the tides of battle. here is a great article on them-
I understand there is a possibility that there could be initials, but as you pointed out, not too many German names ending in 'X'. Curiously, these markings are etched, not stamped as an official marking would be, unless done afterwards, as you pointed out, perhaps in reverence to a squad or troop. I can say that the pics do distort the etch a bit and I believe that both marks are made in the same style and by the same hand (whether contemporary with the weapon or much later, who knows?). I thought of museum acquisition numbers as well until I thought about it (DUH!), they wouldn't permanently mar an item in a collection in this way. In any case, it is exciting to try and research, even if it amounts to not much.