When Game of Thrones meets Mario Kart in a manner as perfect as this, you need to suck it up and spend the money. This excellent design costs $10 plus shipping and is available at Shirtpunch.com until midnight Eastern tonight, at which time it effectively gets blue-shelled into oblivion.

You know you want one.

UPDATE: Buzzer sounded. It's history at Shirtpunch. BUT...if you're willing to pay a lot more ($25), the artist sells the same design at RedBubble. At least you get to choose the color.