Man, hunting down crossover merch between Pikachu and Mickey Mouse feels like a treasure hunt! The best spots I've found are niche online stores like Etsy, where indie artists create custom mashup designs—think Mickey ears with Pikachu’s lightning tail. Hot Topic occasionally drops pop culture collabs too, though you gotta stalk their releases. Don’t sleep on Japanese merch sites like AmiAmi either; they sometimes get exclusive Disney x Pokémon goods during special events.
For physical stores, check out BoxLunch or Kinokuniya if you’re near one. They often carry limited-edition items. Oh, and conventions? Artist alleys are goldmines for handcrafted pins, stickers, or even plush hybrids. Just be ready to elbow through crowds—those gems sell fast!