Sears offers the Sealy Posturepedic Anaheim Ti Firm Queen Mattress, model no. 50867651, for $259.99. Coupon code "SEARS5OFF50" cuts it to $254.99. With $69.99 for shipping, that's $265 off list and the lowest total price we could find, although we saw it for $3 less last month. Note that no box spring is included.
Of note, Shop Your Way Rewards members will earn a Sears credit with this purchase and may be eligible for additional credits and discounts.