Alright, as for finding one, I would just keep up to date with eBay. Bricked and/or skinless Pleos come up for sale occasionally, you could also opt for an untested Ugobe with bad skin (these often sell for $50 or under) and then skin it for the presentation. If you go this route, the Pleo may even end up working with a new battery so the children could see it actually operating without the skin. The actual touch sensors on the Pleos are the silver/copper colored foil (foil is different colors on different models), so the children might enjoy petting the different sensors and watching the Pleo react if you get a working one.