Apparently I only had two t-shirts left, so I've ordered a few new ones. I designed the prints myself, and you're welcome to use them too.
They're CC0, just like most things here. I've only uploaded the png files in sufficient size for a shirt print. Tell me if you want the svg versions and I'll send them to you. A couple of them have variants, as you can see. I only ordered three shirts, though. Not even one of each.
Browse them at your own leisure.
-- CC0 Björn Wärmedal