I know buckle.com sells them, but do you have a Buckle store in the U.K?
and here's search of the brand in the store..
just click on t-shirts, jeans, etc. on the left hand side, and their products will show up.
I don't they have an official website. I haven't been able to find it, but I buy their stuff from the Buckle store where I live.
Here's a pretty cool shirt I just got....http://www.buckle.com/product/produc...00&N=942+26+42
But yeah, if you need any more help just ask.
mmawarehouse.com has some nice clothes also.