I just posted about this on RPGPUB, but I thought this might be useful to other members of the jam who don't hang out there:
I've made SVG versions of MSJX's OSR logo (the one used as the cover for this jam) and uploaded them to OpenClipArt.org. The original logo is in the public domain, and by uploading to OpenClipArt I've released any claim I might have to it, as well.
Black version: https://openclipart.org/detail/335996/osr-logo-black
Blue version: https://openclipart.org/detail/335997/osr-logo-blue