Well you could always look forward to the new GP32 Screen Protector from.... gamepark. Yes, thats right you get a free one on every GP32. well you know its comes on there. Tho they did a shitty job of placing it on mine.
Im gonna try to find out what the best solvent would be for the anti reflective stuff, mine is pretty scratched at the moment. I'll try to find a replacement filter as well.