eBay with vipoutlet has the Member's Mark Insulated Trunk Organizer w/ 30-Can Cooler (Black Marble) on sale for $15 - 10% off auto-applied in cart = $13.50 with free shipping. See reviews at Sam's Club.

Dimensions: 30" L x 17" D x 15" H. 6 mesh side pockets. Velcro closure, includes 2 tie-down straps & hook.