If you thought the teacher might find the extra effort appealing, you could hand write on papyrus, though I’m curious if it would take ballpoint pen well. Papyrus is basically layers of plant fibers pressed and dried together, which doesn’t sound like ballpoint would work well — though I’ve never tried it. You might have to get a fountain pen.

As for where — the Internet has everything. I did a quick search and found some at http://www.dickblick.com/zz112/39/ — I’m sure there’s more out there.

It sounds like a really neat idea, but do the book work first!

Good luck, I hope someone else here knows where to find the paper for you.