With orders of $25 or more, Amazon offers the Dr. Scholl's Men's Comfort and Energy Massaging Gel Insoles for $9.89. Clip the $3 off coupon on the product page to cut it to $6.89. With free shipping, that's the lowest price we could find by $3. They fit shoe sizes 8 to 14.

Note: This item is offered as part of Amazon's "add-on program" and can only be purchased with an order of $25 or more.