I don't think there are any resins available generally that you can print and then wear in your mouth, although Invisalign seems to have come up with a proprietary urethane material they use for their orthodontic system:
I'd suggest making it in whatever resin you can get to work with your $60 DIY machine (good luck with that), molding it, and casting it in Steralloy plastic Steralloy - HAPCO Inc., which is supposed to be biocompatible (which is different from "food-safe"). Or just break down and let the dentist do it - I don't think you're really going to save money trying to do this yourself...