I've just done it in the one size, it should display decently well though or drop it into a graphics program and a little sizing and cropping should do the job. Trying to keep a version with every monitor size out there would drive me a little batty.
Updated the license info (sorry about that). I'm absolutely fine with you doing that, I generally don't mind people using my textures for whatever as long as it isn't commercial. Thank you ever so much for checking in first though.