Disney don't make Ukuleles but have had hundreds of Ukuleles made for them to promote various movies, TV shows, characters and other activities over the years. 

The Ukulele quality is usually pretty low end but there is a large market for them from people who collect Disney memorabilia which inflates the value so I'm not going to try and list the models, just point out they exist. However it is worth remembering that sometimes Disney got a respectable manufacturer to make them, (like USM who made the Mouseketeers Uke) but more often they got a toy maker like Mattel, Peter Puppet Playthings of NY, (who made the Davy Crockett bell), or First Act, (who made the Toy Story 3 and other Pixar themed ukuleles)