Not sure how many people you're expecting, but we ordered both machines off amazon a couple of years ago- they were the cheap ones- under 50 bucks each, and they work fine the couple of times a year we use them.
My wife has both, popcorn popper and shaved ice machine. Shaved ice kicks as over regular snow cones. We are in H.B. And she does rentals, kid carnivals, wedding, etc. PM me and I will get you hooked up.