I've decided to give out the full resolution designs for my merchandise. With some transfer paper, an iron and a shirt you can make your own replicas of the stuff at rubensim.com
Watch Nerd City's video here: https://www.youtube.com/watch?v=ywcY8TvES6c
Example of ironing a design onto a shirt using transfer paper: https://www.youtube.com/watch?v=AXCh6rW2LbY
I'm not affiliated with or sponsored by Photo Paper Direct, but they seem to have some pretty solid deals on transfer paper on their website.
####
https://i.imgur.com/7Gt6bog.png
Default Lisa
https://i.imgur.com/Q3s2eZP.jpg
Supreme Leader Dave
https://i.imgur.com/gEE3Ij8.png