Could the shirt be created, with approval from the U, as a one time fundraising strategy? Buy a ton of them low and sell them for double. More options might turn into more money. Instead of just asking people to donate, give them options. If there is a stand or something, there's a good chance a few people might toss a few bucks into a donation can. However, the door would be open for more to donate/ each donor to give more if they get something tangible in return. Finally, some people who aren't interested in donating might just buy the shirt because it's cool (that's still money towards the project)?

Disregard if this idea was already kicked around. I donated and then have only followed the project via the email update i receive.