Make your own!

https://store.flitetest.com/ft-simple-cub-mkr2/

This one’s technically foam, but it’s a very cardboardy foam. With a little bit of carbon fiber reinforcement (provided) it’s surprisingly durable and MUCH simpler and easier to build that a balsa or fiberglass airplane.

After building and flying one of these, I can certainly believe that cardboard/foam construction is great for a “disposable” (single use) airplane or even for a couple of missions - knowing that the life span will be short.