Kadtrampo recommends Carite Balance/Trampoline Shoes from this site in Denmark:
It’s hard to believe that 40 years have passed since Hazel and Kaj Carstensen set up their business to sell specialist Danish leotards and gym pants by mail order
Operating from a garden shed in ‘the back of beyond’ Carita House soon became popular with gymnasts and fitness enthusiasts who appreciated the quality, style and the unique ‘Carite®’ fit which really stood up to the action. …
Gymnastics Coaching.com 