Hi. What's your budget? Last time I talked to the guys in Gobles, a Lyman BP rifle ran about $800. I was looking at flintlocks, but percussions are about the same. Mind you, $324 will buy you a TC Impact from Bullseye Sports on Wharncliffe. Haven't been in there, yet, so I know nothing about 'em. Live just down the street too.
Add the W's. .bullseyesports.ca/long-guns/black-powder-rifles.html
Suggest you buy a copy of Lyman's BP Handbook and Reloading Manual first. It's a good read and will tell you all about BP firearms. Starting with they get loaded in grains by volume.