I designed and printed a handheld gimbal for my GoPro Session 5! It was an interesting experience and I learned a ton! You can download the model and try printing it yourself!
Software: cad.onshape.com
3D Model https://www.thingiverse.com/thing:292...
Gimbal controller: http://www.goodluckbuy.com/mini-alexm...
Gimbal frame and motors: http://s.click.aliexpress.com/e/3bEU7MB