With orders of $25 or more, Amazon offers Prime members the Hoppe's No. 9 Shotgun Cleaning Kit with Aluminum Rod for $4.46 with free shipping. (Non-members can spend $35 or more to qualify for free shipping.) That's the lowest total price we could find by $14. It comes with a 4-oz. bottle of cleaning solvent and a 2.25-oz. bottle of lubricating oil. Brushes aren't included.

Note that this item is part of Amazon's "Add-on program" and can only be purchased with an order of $25 or more.