Costco member in the States? Try costconext.com.
I have not compared CostcoNext's pricing against other outlets but, if you're shopping premium brands, might be worth a click. (Stumbled across this today on reddit in a discussion about Costco perks.)
Brands in which travelers may be interested:
Anker, Baggallini, Briggs and Riley, Jack George, Klymit, Nomatic, Weatherproof.