Walmart offers the Outdoor Products Ditty Bag 3-Pack in assorted colors for $4.97. Opt for in-store pickup to dodge the $5.99 shipping charge. That's $10 off and the lowest price we could find. This set includes 4" x 9", 5" x 11", and 6" x 13" water-resistant bags.

Of note, Amazon charges the same with orders of $25 or more.