In order to build the GoPro VR holder yourself you will need the following STL files and the below parts from McMaster-Carr.
This is shared under a CC ShareAlike-Attribution License V2.5, see Here
You will also need:
McMaster Part Number 90725A025 -- Quantity 13
McMaster Part Number 92005A223 -- Quantity 13
McMaster Part Number 94811A029 -- Quantity 1