Seems like it. Hope he's getting a volume discount, a thousand of the LED modules (didn't he say five band members someplace?) is enough of a purchase that they ought to be willing to work with you on pricing. However, it is going to require a pretty decent amount of power for 600 LEDs per suit (RGBx200). The spec says 60mA each, so your power supply is going to need to be pretty gutsy without weighing a ton.. 200 times 60mA is 12000mA or 12A. That's a pretty good load for any battery.. I wonder if the Super Capacitor jobbies might be good for something like this, or if LiPo or something cheaper is just as good. It's a stage prop and not going be used every day, it hardly needs to be "green" and could use alkalines or whatever. I'd assume the performance times are relatively short, and fresh batteries could be swapped in during song breaks if needed.
How do you envision driving the patterns? Since you are connecting to a PC, I'm assuming there's either a human "lighting operator" or software.. are we talking about a set sequence, or something that is changing on the fly, like in reaction to the music or what have you?