It's important to start out solely with a rifle that pleases YOU. Price, caliber and style need to meet your criteria, which at this point seem to be simply something to give you good practice in handling a flintlock reliably enough to hunt confidently.
There's always someone who puts a damper on the initial enthusiasm by asserting that that you're interested in is not period correct, and you need to spend beau coups bucks on a proper custom build - pure BS, since there's time to learn and grow with a "lesser" :shake: correct rifle. Get something you'll be satisfied to start out with. A rifle you can learn to handle. Through handling, carrying and firing, you will discover, without the distracting coaching of experts, more about what you want, don't want, or want to find out about.
Once you have more questions, there will be a plethora of folks here ready to point you in a myriad of directions. There are precious few here who would seriously look down their nose at any choice of rifle you make, or would disparage any of your questions or concerns about learning or growing in flintlock shooting. Not everyone has the deep pockets to own truly authentic styled rifles.
Would you consider a Mercedes, Jaguar or Porsche as first car to learn on? Maybe some of you would be so foolish, but not realistically in my world.
Start "cheap". Learn what will make your production line gun perform better, spend time getting to know it, and you can progress from there.
The learning curve for you at this point in time is to learn the mechanics of how to make your flintlock, of any design or price, perform to your satisfaction. Leave room to grow for later.
As already mentioned, take a look at the rifles in the classified ads. Prices will be genuine bargains, and everything there would be more than a capable choice to begin with.
I've been shooting percussion rifles since the late 60's. I have a .40 cal. rifle my Dad and I finished in 1970. The first rifle is an accomplishment not to be ignored, plus it's great fun to shoot.
I've always preferred halfstock rifles, and have a couple of the Investarms Cabelas models. They were used, and affordable for me, and are capable shooters.
Last year I got a new Lyman Great Plains flintlock. With proper break-in, a little tuning and tweaking, and it performs for me every bit as well as would a pricey custom-built.
Someday when I retire and have plenty of time to devote to a scratch build, I'll make my dream rifle. Meanwhile, I'm maintaining and building proficiency with what I already have. I never feel under classed or under gunned at the range. Not even amidst the custom-built shooters. They are, with rare exception, an understanding bunch.
