It sounds like you are shopping the Discount Tire store website. If so, this tire will not be listed as the Discount Tire stores do not carry this tire in stock, however they can order a set for you.
As far as specials go, today and tomorrow you will receive $75.00 back by mail with the purchase of four STT Pro tires during the Memorial Day Deals sale. You can save an additional $60.00 back by mail if you purchase using Discount Tire credit. See the links in the OP for specifics.
Discount Tire Direct (mail order/online service of Discount Tire Co) has the 40x13.50R-17 STT Pro in stock; ready to ship. The same savings noted above apply :thumb:
Details:
40x13.50R-17 Cooper Discoverer STT PRO | Discount Tire Direct