First, I'm sorry for my tardiness, I haven't been able to connect to the site.
Thank you Joe S. for the Ruxton connection. That fills the bill for a late style half stock rifle originally made in flint better I think than anything that has been referenced to me before.
Still the article states: "A flint lock on an American half stock plains rifle is definitely a throwback." and
"I don’t expect collectors will find many other original, flintlock, halfstock plains rifles out there. I sure wouldn’t hold my breath waiting for somebody to turn up an original flint, half stock Hawken. This flintlock Henry halfstock may very well be one of a kind, or one of very few. That makes it a pretty rare piece."
That sums up my feelings, yes there were a few late half stock flintlock guns made, but they were exceptions, not common.
Boompa, no one doubts that there were flintlock Hawken rifles, the doubt is about flintlock halfstock Hawkens.
"Logically at least a few half stock guns were built using flints. Many simply preferred the flintlock."
I have had it explained to me by someone with unquestionable credentials, that we can extrapolate history by logic when we lack hard evidence. So, since we know that the Hawken shop would build anything a customer would pay for, we know they built rifles, we know that there were telescopes and that they knew about them, we can logically ask "What is the right telescope to put on a half stock Hawken flintlock?" See where logic can take us?
But seriously, your original question was what would be a good lock choice and Joe S. has posted us a connection to what is probably a very good example of the kind of lock that would really fill the bill and a good look at an original rifle (even though not Hawken) appropriate to the time period.