just have your lawyer draft up a disclaimer that says they are going to be for movie and novelty purposed only, and that they are not government issued id's or drivers id
well i made one for my friend and he uses it a few times a week, even if you looked for where it said novelty its hard to see, its really small and on the bottom in transparent type.
I think you could get in trouble if you tried to use it and it said novelty item on it, and you would probably get you in trouble anyways if they knew you made them even with the novelty item thing