This is the new version of the 3-axis gimbal for the GoPro camera. It is available now, but still in beta testing. More documentation will follow soon.
To complete it, you will need 3 servos "Turnigy 180D", available at Hobbyking,
and three ball bearings with 10mm outer diameter, 6mm inner diameter (also from Hobbyking or from various RC shops, AliExpress.com, eBay, etc.)
As the parts fit quite precisely, you may have to clean excess powder by scraping edges carefully with a fine screwdriver (e.g. the clasp that closes the cage), and carefully push parts together by working them in and out in multiple steps. This is only necessary at the beginning, they will soon fit much more smoothly as they wear in. The servo crowns are best assembled by slightly pushing them into the holes and pulling them in slowly with the center screw.