If we ever get any users who are knowledegable about flintlocks, then we should allow pages featuring those guns. But so far, we haven't had any such users, at least none that I've seen. Though my Dad is big into flintlocks and black powder weapons, so if only he wasn't such a Luddite, I could get him into IMFDB.
Also, I have pictures of a Trapdoor Springfield flintlock pistol that was used in "Pirates of the Caribbean", which came from my contact at ISS. Unfortunately, I can't post it because the page for that movie keeps getting deleted.