How to make a paper flower durable enough to put on a ring?

I want to make a paper rose (made with ordinary paper, not tissue or crepe paper) durable enough that it can be wearable on a ring. I've found information about Smooth-Cast 327, but I would like something cheaper and that I could buy at a craft or home-improvement store (Smooth-Cast 327 is about $26 and must be ordered online).