Weird request: balloons

[RedMage]

OK, here's the deal: the children's ministry for the mission trip to Mexico I'm going on needs balloons for games. Problem is, one of our team members is allergic to latex.

I can't find any non-latex balloons that aren't really expensive (like 50 dents to a dollar per balloon) and none of them will work as water balloons.

Our allergic comrade could sit out of all the games we do with the kids that use balloons, but that would sort of stink for him, and depending on how allergic he is, it may be possible for him to have a reaction if a person who touched latex touches him. Plus, I never anticipated it being this hard to find non-latex balloons, so I semi-volunteered to get them.

Anybody have any advice to offer?