Recently at conventions we discovered a new service called ArtWorkTee. As you can probably guess they specialize in designer t-shirts, not only with some well-known properties (like My Little Pony: Friendship Is Magic) but also t-shirts featuring some well-known Furry Fandom characters like Telephone and Majira Strawberry. You can find them at various Furry and other Fandom conventions, or check out their web site for some of their latest available designs.