I've been using a cheaper MC-30 clone for some time now. I bought it for use with my F5's and I still use it with both my one remaining F5 and my D700. It was so cheep that I bought several in case of failure but have never had to use the backup.
I also have a Vello wireless shutterboss which uses a cable with a 10 pin connector for the camera and a 2.5mm stereo connector for the shutterboss side. In either case they have the 1/2 depress / full depress button functions work as they should.
I'm not familiar with Elinchrom skyport but in order for the 1/2 depress / full depress button functions work you would need stereo connector on the 10 pin cable and the Elinchrom skyport would need to support the stereo plug connector. If the 3.5mm connector on either the cord or the Elinchrom skyport is a mono type it can't support full functionality for the camera focus / shutter release.
Vello does sell their cables separately, if you need a 3.5mm you would need a 3.5mm to 2.5mm adapter. I'm not sure where you would buy one in the U.K.
Vello 10 pin cable catalog #RCC-N1 / MSRP $10.00US. Also I would think Elinchrom would sell their cables separately.