+1 for Chambers Flintlocks - Pick up a copy of Muzzleloader magazine. Lots of sources for all the extras you'll need and some great stories of the era.
New quality flintlocks are pricey. Made by true artisans using many lost arts. I was fortunate to find a LH one made by a well known maker for a very reasonable price. It should be on the wall rather than in the safe.
Kits are available from a few sources and very satisfying to build.