I had a brown bess musket a few year back that I ended up selling to the gunshop. I used her mainly for clays and re-enactment, but did manage to take a few pigeon and rabbits on occasion. I now quite fancy a muzzle loading rifle for small game, but have no idea where I stand with the law on this. You can buy quite modern looking ones these days, but I'm a traditionalist in most things I do, so would stick to wood and blued metal.
I guess my FEO could argue that I don't "need" it and I should just stick to conventional rifles, but I personally like muzzleloaders and like the added challenge. I hold a relevant explosives licence for black powder so I have that part taken care of, I just have no idea if I would be allowed to hunt with one.