Mickey Mouse Ears are likely the most popular souvenir purchase at the Disney Parks. You can find them at all four theme parks and at Disney Springs as well. They’ll be shelved in stores and hanging at outdoor kiosks.
Monogramming/personalization is available at Mouse Gear in Epcot, the Chapeau in Magic Kingdom, Adrian & Edith’s Head to Toe in Hollywood Studios and at Disney’s Wonderful World of Memories at Disney Springs.
There are several styles to choose from. Prices start at $13.95. There’s an additional charge for monogramming.