Sears offers the Craftsman 18" Bolt On Storage Bag, model no. 009-16896, for $18.96. Opt for in-store pickup to avoid the $5.99 shipping charge. That's $11 off list and the lowest price we could find. It features 15 pockets of a variety of sizes.
Of note, Shop Your Way Rewards members will earn a Sears credit with this purchase and may be eligible for additional credits and discounts.