Mr. Brush is only available on our TeePublic.com store. Lots of shirt styles and color options available. Buying t-shirts and stickers (and of course magazines) helps us offset our printing costs, which are super expensive. Buy one here.
We do all of our own one-color t-shirt screen printing here at Gnarly Industries, but, for full color direct to garment printing, we let other people take care of that for us.
Here's a note from TeePublic about their printing technique: