Judging by the style and hardware I'd bet on the company that makes the Arrow suits for the jacket. You can count on anywhere from at least twelve to eighteen hundred for a jacket from them, and that's only if they're allowed to make the jacket while the show's on the air. Looks like it was based on a costume sketch I've seen so it's probably not one of their in house designs, which they would have more leeway with. Otherwise, I'm sure there will be replicas popping up here and there. The link above has nothing to do with the filmjackets website, just some fly by night company trying to cash in on someone else's work. I'd steer clear of any site that can't show their own work, just movie stills, promo photos, or pics stolen from legitimate sites. I'll keep my eyes open for more reputable companies that do a replica of this one.
Pants look like dark brown cargos in some shots and like some sort of dark brown striped camo in others. The camo looks better/more interesting to me but no idea where you'd get them.