Staples offers the Jansport Vector Accessory Pouch in Black for $6.39. Opt for in-store pickup to avoid the $9.95 shipping charge. That's the lowest price we could find by $10. It measures 3" x 7.5" x 2.5".
Crocs via eBay offers the Crocs Unisex Modi Sport Realtree Max-4 Flip Flops in Chocolate/Khaki for $22.99 with free shipping. That's the best price we could find by $9. They're available in select men's sizes from 4 to 15 and women's sizes from 6 to 10 12.