You could probably find really cheap plastic plates somewhere... the grocery store, the dollar store... And then decoupage the images face down on the bottom of the plate and seal it. A LOT. I don't know how it'll hold up to washing, but I love the idea.
This is a AWESOME idea! I might actually do this to some sushi plates and then put it in a box as part of a "Sushi-in-a-Box" dealio. I need to add the decoupaged plates somehow. Too good an idea to pass up.