Well... you have to buy it from Hannah Montana and the other person, that knows this guy, and buy it from that Hannah Montana.
Most Hannah Montana/Miley Cyrus merchandise are at Wal-Mart.
You can't it was made exclusive for Hannah Montana and Disney never merchandised it.
Buy a backstage pass and meet Miley Cyrus/Hannah Montana.
You have to buy one just like everyone else on a Hannah Montana tickets .com.
Sadly, you can't buy them. They ARE adorable, but un-purchasable. Here's an article about the designer: http://www.film.com/movies/hannah-montana-the-movie/story/fashion-film-hannah-montana-movie/27179605
Try FashionTIY.
it is already on DVD
you can buy them from the Disney shop!!
you could go on ticketmaster.com
on the website.
go to the store and buy it