A best bet is the Reebok Women's Workout Ready Mesh Shorts in four colors (Aubergine pictured) for $12.97 before the above coupon, $8.43 after. (This price will increase after 2 pm ET.) With free shipping, that's the lowest total price we could find by $2. They're available in sizes XS to XL, although not in all size/color combinations.
Note: After 2 pm ET, the coupon will only yield an extra 25% off. After 4 pm ET, the coupon will then yield an extra 15% off. Coupon expires today at 6 pm ET.