I wouldn’t say “super easy.” It’s certainly in the realm of what’s possible for a normal person who is good with their hands, but that’s not everyone. A lot of people seem to conflate “possible” with “really simple” when it comes to handicrafts like this.

The powder in particular is quite tricky to do well.

Black powder firearms also do not require any paperwork, except in New Jersey. Can have them shipped to residential addresses too. They are occasionally bought by convicted felons who want to defend themselves but cannot possess regulated firearms.

I recommend .44 caliber cap and ball revolvers of the “Remington 1858” design. More robust than the Colts and the .44 is more effective than the smaller calibers in this case.

EDIT: You won’t be looking to spend top dollar for actual antiques, if that wasn’t clear. Modern functioning replicas, mostly made in Italy by Pietta or Uberti, are both available and reasonably priced.

Maybe buy a printer off the used market with cash, print a large amount to last you a while, then sell the printer off again. You would have to manage your stock of flyers as a sort of contraband i.e. hide them, but that’s probably more convenient than “tainting” your personal printer and having that risk laying around your home.

If you do end up participating, printer steganography is something to be aware of. I never knew about this till fairly recently, and I think it was a comment here that informed me.