Have a pair of ovaries and family members have guns, so here are my 2 cents:
Lucas would have to pass the safety course and fill out said RCMP firearm license to get a NON-restricted firearm. Basically most hunting rifles or shotguns. If he wanted a handgun or semi-automatic rifle/shotgun he'd have to get a restricted firearms license which is quite a bit harder to get and has way more oversight. You can only own a restricted firearm for collections, target practice, or competition shooting.
I'd wager he has a non-restricted license cause of that dinky little rifle he has, and because it's easier to get. The safety course is generally 125-175 dollars to take, so the grift money was probably used for that. The restricted license course is more expensive, but idk how much it is. You need to have an 80% average on the non-practical portion and pass the practical portion. You then need to apply for the license (fill out the RCMP forum), pay the fee, mail it, and wait for it to be processed, which takes at least over a month. I find the RCMP fill-in and mail thing a little concerning because he doesn't have to explain to someone face-to-face why he wants a gun. He just has to fill in the form. Wouldn't be surprised if the shmuck who has to approve licenses approved him just to avoid any hassle tbh.
He'd also have to buy it. Based on the gun he has he probably just went to Cabella's or some shit. They carry some hunting rifles, and I can't see Lucas fitting in at the few actual gun shops around (at least where I live).