Not going to go there. So much has been said about different makers and their guns and how authentic they are, and what is and is not PC, that it would all be redundant. I suggest you use the Search function of this site and type in "Early Rustic Arms". Here is one thread
thread
I have seen several different stances on Period Correctness exhibited here and I will over-simplify to attempt to categorize the different points of view. None of these points of view are "correct", they are just different points of view!
1) "Nobody really knows what they had anyway. This one's a a flinter (or a percussion, or a matchlock, or a snaphaunce) and they had those kind of guns then, so it's right and anyone who says otherwise is just spoiling everyone's good time." Excellent functioning guns that would work for a "1" type person could be had for as little as $200. Or "fantasy guns" that fit this category for me could cost $25,000.
2) "I like my guns to be similar to those used in a particular time and place. The barrel on this one is the right length and shape (octagon, or round, etc) and approximate caliber, it has the right kind of wood and a lock that is kind of similar to those used in that time and place, the furniture is similar, the overall architecture is similar, and it's not worthwhile to me to pay for expensive extras like correct barrel profiles, or small details that experts use to date and locate period pieces." Guns that would work for these criteria are not going to be available as cheaply as above at the low end- maybe $400 would be the bottom. Again, sky is the limit.
3) "I love to do the research or am willing to pay those who do, and try to get my kit to look like actual examples of existing historic pieces. The details are very important to me. If I found that a certain feature of a gun that is advertised as representative of a certain time and place could not really fit in, this would bother me. I'd rather go the extra mile, pay the extra money to get it as close as we can. But I ain't going to pay for a hand-forged barrel." Even in a plainly finished gun, it's going to be hard to get below $800 here at the low end, in my opinion, unless it is a plain, later period trade gun. Again, the sky is the limit.
None of this is meant to inflame. But it would help us to help you, if we knew where in that spectrum you are.
Remember- advertising is written to result in sales and 3 different people reading the same text, looking at the same website or brochure will react differently, every time.