Print on your favorite open-source 3D printer. The two fiber optic cables are placed within the holder is held in place with a set screw.
Use thumb screw from http://www.thingiverse.com/thing:30500 to attach it to an 8mm smooth rod.
If you need the base go to http://www.thingiverse.com/thing:28133
Full information here
Thanks to Chenlong for the designs.
This component is part of the Open-source Optics Library: Zhang C, Anzalone NC, Faria RP, Pearce JM (2013) Open-Source 3D-Printable Optics Equipment. PLoS ONE 8(3): e59840.
This is part of a larger project to reduce the cost of scientific equipment using open-source hardware. Read more here