Sunbeam Heating Pad with UltraHeat Technology, 3 Heat-Settings, 9-Foot Power Cord, Machine Washable Cover, 12” X 15”, Light Blue [Pack of 1] $5.71

Amazon.com has Sunbeam Heating Pad 12” X 15” for 6.72 + Extra 15% off coupon = $5.71.
https://www.amazon.com/Sunbeam-Ul…B00006IV4N
Not the lowest ever, but a very good price (considering that it’s not an add-on only item).