I've been building a lot of electronics for props lately and it occurred to me that one doesn't have to spend a lot of money (or order on-line) for project boxes. I've been using basic plastic junction boxes for a number of devices and it's worked out great. The single gang type costs somewhere around $.25 at most hardware stores (the dual gang is more like $1.50). Add a cover plate for less than a dollar and you're in business.
I hope someone finds this helpful!