This one will be difficult to acquire
Well, at least the dev team one.
Posting says:
Official illustrated poster commissioned by Crystal Dynamics and Square Enix to promote the upcoming game for global print, covers, and a special gold-foil variant just for the developers. There?ll be more info soon on when and where you can get your hands on the 18?x24? poster and I?ll have some fun behind the scenes pics on its creation in the near future.
So it might be one of those Treehouse will sell?