The cut on those pants is awesome. I really like this fit, sans the square. That orange/white palette doesn't fit with the tie at all. And because I think that tie works well, I'd opt for a different square.
@GBR Wow man,different strokes for different folks. No need to be dick about it.
Keep in mind the guys at GQ tailor the shit out of the clothes in their shoots. So you're very unlikely to find it anywhere near what it looks like in the linked pic. You could also contact the folks at GQ to find out where you might find it.