The bands had perished on mine but were 'sticky' enough to still retain the style. I used those small clear bands that are used to hold most modern action figures into their packaging. They held the hair really nice and tight.
Obviously this won't help you with the restyle but they are good option once you get the style back.
"I should say I`m very much cleverer than any of the people who put me here. As a matter of fact, I could leave any time I wanted. It`s only a doll`s house after all. Anyway, I don`t mind. I like dolls" - The Mad Hatter, Arkham Asylum.