"How did these items get made if there's no way to learn magic? Are the magicians homeschooling their children and not writing any books? How did you learn?"
"Half this stuff is antiques," says the shopkeep. "Look, asking me a dozen times isn't gonna make the answer more to your liking. I don't have Hogwarts in the basement, deal with it."
"But where do you get the stuff that isn't antique - who made the Avalon itself? - isn't anybody panicking about the medallion supply? -"
"Kid, nobody knows how to make medallions."
"But some people apparently know how to make luck charms and protection amulets!"
"I'm not going to give out my suppliers' personal information. I wouldn't do it even if you weren't annoying."
"There have to be books -"
"Does this look like a library to you?"
After about five minutes he says, "...Could you stop suppressing for a moment? I want to hold this a little more precisely and also see what I've already written."
After about another ten minutes of careful scribbling he says, "...I think I've got it."
She turns the flashlight on behind the plastic wrap, makes sure nothing is stretched, and presses the face of the light directly against the floor so it's not distorted. She incants to boil the teacup.
"It works," Kanimir breathes. "And also I'm feeling very self-congratulatory on my ability to inscribe that small, but it works."
She kisses him. "I'm very impressed. We should get some bits of glass or plastic yea big," she taps the flashlight face, "to write on for permanent light diagrams."
"Yes. ...Assuming that was the actual projection you were incanting from and not just the plastic, that just occurred to me."
She boils another teacup.
"...It was either the projection both times or just one of them, but that means projections work either way."
"And - and - since the projection counts as novel human intervention! - we can machine produce the glass parts!"
"We'll need capital before we can acquire the machines to do so, but--yes. Yes, we can absolutely do that."
"Tacky. I guess there'll be a market for that once there are enough people who know about magic."
"I'd say 'there are girls who would like that sort of thing' but it sounds sexist when I actually consider saying it out loud."
"I imagine boys who liked that kind of thing would choose not to buy it anyway for various cultural reasons, so it's not an inaccurate summary of the market segment, anyway."
"Eugh. I'll stick with wood. Possibly decorated wood, but something tasteful. Silver wire and semiprecious stones maybe."