You're welcome to use almost any site as long as its not eBay, due to not having standardized pricing on their site. 

Below you can find a list of valid sites to use as your product link:

• Abe's Market
• Ace Hardware
  
• Active Forever
  
• Adam and Eve
  
• Adorama
  
• Advance Auto Parts
  
• Amazon
  
• Anthropologie
  
• Ashford
  
• Asos
  
• AutoZone
  
• B&H Photo
  
• Babeland
  
• Backcountry
  
• Barnes & Noble
  
• Beauty.com
  
• Bed Bath & Beyond
  
• Belk
  
• Best Buy
  
• BestDirect
  
• Big 5 Sporting Goods
  
• BJs
  
• Bloomingdales
  
• Bluefly
  
• Blueshop
  
• Blush.com
  
• BodyBuilding.com
  
• Bon-Ton
  
• Boston Store
  
• Brookstone
  
• Cabela's
  
• Canadian Tire
  
• Candy Warehouse
  
• CarID
  
• Carson's
  
• Chef's Catalog
  
• Condom Depot
  
• Condomjungle
  
• Costco
  
• Crate and Barrel
  
• CVS
  
• Dermstore.com
  
• Diapers.com
  
• Dick's Sporting Goods
  
• DirectCanada
  
• Dillards
  
• Drugstore.com
  
• eBags
  
• EdenFantasys.com
  
• Eggshells Kitchen Co.
  
• Fab.com
  
• Fanatics.com
  
• FansEdge
  
• Folica
  
• FragranceNet.com
  
• Frys.com
  
• FutureShop
  
• GameStop
  
• GNC
  
• Golf Galaxy
  
• Gurney's
  
• Hairenvy.com
  
• Hay Needle
  
• HH Gregg
  
• Home Depot
  
• Hookbag
  
• HSN
  
• Indigo
  
• JCPenny
  
• Jomashop.com
  
• J&R Electronics
  
• JTV Jewelry Television
  
• Kay Jewelers
  
• Kmart
  
• Kohl's
  
• Land's End
  
• Lens Crafters
  
• Lids
  
• Linen Chest
  
• Linens N Things
  
• Lowe's
  
• Macy's
  
• Mainstreet (Aprons)
  
• Marketview Liquor
  
• Meijer
  
• Mikasa
  
• MGA Entertainment
  
• Nature Hills Nursery
  
• NCIX
  
• Newegg
  
• Nordstrom
  
• Office Depot
  
• Office Max
  
• Overstock
  
• Peapod
  
• Pearle Vision
  
• Pepboys
  
• Perfumania
  
• Petco
  
• Petsmart
  
• Pfaltzgraff
  
• PinkApple
  
• Pottery Barn
  
• Pro Sports Memorabilia
  
• QVC
  
• Radio Shack
  
• Rakuten
  
• REI
  
• Ross-Simons
  
• Saks Fifth Ave
  
• Sally Beauty Supply
  
• Sam's Club
  
• Sears (*Sold directly by Sears only)
  
• See Jane Work
  
• Sephora
  
• Shoebuy
  
• Shop.ca
  
• Shopbop
  
• Sierra Trading Post
  
• SkyMall
  
• SOAP.com
  
• SportsMemorabilia.com
  
• Sports Authority
  
• Sports Unlimited
  
• Staples
  
• Steiner Sports
  
• Stokes
  
• Summit Racing Equipment
  
• Sunglass hut
  
• Sur La Table
  
• Target
  
• The Company Store
  
• The Container Store
  
• The Source
  
• The Vitamin Shoppe
  
• Tiger Direct
  
• Toys R Us
  
• Ulta
  
• Ultra Diamonds
  
• Uncommongoods
  
• US-Mattress
  
• VINE.com
  
• Vitacost
  
• Wag.com
  
• Walgreens
  
• Walmart
  
• Wayfair
  
• Well.ca
  
• White Flower Farm
  
• Wine.com
  
• Wine Library
  
• Workout Warehouse
  
• World of Watches
  
• YoYo.com
  
• Zales
  
• Zappos
  
• zZounds