Bleacher Noise Makers

this is a question for anyone who sits in the bleachers at the games....i was wondering how could i get my hands on one of those green and gold noise makers u were using?  i don't sit in the bleachers, though i'm gonna have to try it out some time....and trying to get the crowd (in other locations) as involved as possible can be difficult at times, and i was thinking the noise maker could help out - along w/the horns me and my buddies already have.