I don't have contacts, but maybe ask Phipps, the Carnegie, the Warhol, the Aviary, Science Center (some of those are the same) for maybe a day pass or two, or a membership, or something? They often do stuff like that. There's also that Pittsburgh museum... the Heinze museum? The symphony/opera/ballet always have student ticks, maybe they could offer something similar.
I'm just trying to think along the lines of places that have very cool events who do not always sell out their tickets and thus might be happy for publicity/warm bodies who spend in giftshops/concession stands. Movie theaters too maybe.
(and this isn't OT at all!) (AND it sounds awesome )