The following tip applies to Rover 75 and MG ZT 04 Model Year vehicles only (VIN (Vehicle Identification Number) 4D307061 onwards).
Previously XPart has supplied the complete gearchange assembly to repair faults arising in the mechanism. Unfortunately XPart currently has no supply of the complete assembly. However research and feedback from the AutoService centre network has shown that the faults rarely lie within the mechanism itself but are actually with the cables.
XPart has now successfully re-engineered the cables and they are available individually The part numbers of the two cables are: ULS000021 and ULS000031.
May help someone, maybe Although they don't appear to have any stock themselves at the moment.