The Adidas "Liga" soccer jerseys are pretty cool and they have one that comes in white with navy blue collar and stripes. I've got one in red w/ white trim, but I'd definitely get another one in white to put an X-Marks patch on! They're available at most sporting goods stores like Dick's, Sports Authority, etc. They are made out of a moisture-wicking polyester that Adidas calls "ClimaLite" or something. I paid $25 for mine, but I'm sure they could be had cheaper in bulk from a wholesale supplier or silk-screening place or something.