I'm sorry to say I had a different picture in my mind. But the TB on the RS2k is in a totally different position than it was on the old MFI XR3i...
The throttle cable obviously runs the same way like it does on the Zetec engines. And as the TB sits on the side of the engine the cable probably is longer than the Zetec ones. These might fit as a quick repair solution but it will be much closer to the rocker cover or rubbing somewhere.

The only one that's still available as an aftermarket part is the LHD Zetec 16V cable (Ford 6802721, overall length 1065 mm)


Another option might be a custom made throttle cable like it is used for motorsport purpose. Connections for the RS2k on the acc.pedal and the TB are quite standard I'd say so this should work.