I was walking through the new Petco in Kyle the other night to get dogfood and was suprised that not only do they have a saltwater section, but that it had corals in it. Nothing amazing, but they had zoa colonies, a gbta, and mushroom rocks. The prices weren't stellar and the gbta was totally bleached, but I was surprised they even had them.
Keep in mind that in-store purchases do not have a 15 day guarantee. That seems to be limited to online orders.