CYBER Gadget release on July 29, 2016 in Japan a new game card case which will be compatible with Nintendo 3DS and PlayStation Vita game cards also. In the case you can hold together the two different types of cards. Depends on your setup you can hold 6 Vita or 6 3DS cards or you can mix them.
The case will be available in blue and grey /transparent versions. The price depends on the retail stores.