There are often cardboard stand-ups used for characters on a map when playing a role-playing game. They’e cheaper than minis. Paizo has sets of them they market as “pawns”.
The plastic bases commonly used hold 1/16″ chipboard, perfectly. It’s also numbered 0.06″ or just 0.06. It can sometimes be called Binder’s Board and is used for making book covers. Check the scrapbooking places.
I got a big box of it on eBay – possibly a lifetime supply – for $16, including shipping.
It fits the stands perfectly. I’ll print the art, glue them to the cardboard, and cut them out on the laser cutter at TechShop.