For starters, I’m mad that your forum seems to have eaten my origional account and will not let me in even after repeatedly changing my password. So, here’s a new account.
Anyways, here is a 3d printable tether management spool and control box setup. http://www.thingiverse.com/thing:2293622 It’s currently set to use a tecnec jackreel 4 as the base, and uses the bluerobotics fathom x tether interface board and tether, though others would work fine. There is a slipring inside. The fairlead section is made up of 13mm OD bearings and stainless tube. it seems to be quite sturdy. All the parts were printed in black ABS.
If there is interest, the box could be adaped for use with other tether interface boards.
I’m working on a larger capacity unit as well but it isn’t there yet.
The license is currently set to non commercial, if anyone would like to produce those parts, commercial licenses are also available.