Here's a list from their website. Note that not every location will have the blind box.
Walt Disney World® Resort
Downtown Disney® Area, Resorts and Other
D-Street
World of Disney® Store
Disney's Pin Traders
Art of Disney
Once Upon A Toy
DisneyQuest
ALL Walt Disney World® Resort Hotels
Disney Cruise Line® - Disney Wonder and Disney Magic
ESPN Wide World of Sports® Complex
Disney Earport and Magic of Disney at Orlando International Airport
Magic Kingdom® Park
Emporium
Frontierland Trading Post
Uptown Jewelers
Space Mountain Arcade
Merchants of Venus
Epcot®
Art of Disney
MouseGear
Pin Central
Club Cool
ImageWorks
Disney Traders (at World Showcase Entrance)
Guest Relations
Disney's Hollywood Studios™
Mickey's of Hollywood
Tower Hotel Gifts
Beverly Sunset Sweet Spells
Animation Gallery
Sorcerer's Hat Shop
Stage 1 Company Store
Disney's Animal Kingdom® Theme Park
Island Mercantile
The Outpost Shop
Disney Outfitters
Chester & Hester's Dinosaur Treasures
Dino Institute Shop
Serka Zong Bazaar