Have you checked out Takedown Sportswear yet? They've got some great custom singlets.
There's the American Hero (as seen below), Silverback Gorilla, Haulk (Incredible Hulk), B-Man (Batman), and a cool Armed Forces one just to name a few. They also have wrestling shoes, gear, and apparel.
If you follow Takedown Sportswear on Twitter or Facebook you even have the possibly of winning free wrestling gear. I won the singlet pictured above and it's really nice.
If you need custom gear, or if you just in the marking for some wrestling gear in general, check them out.