Z-Spar spinnaker car for integral exterior track

[suiramor]

In looking at how to add whisker pole attachment to my mast, I realized that the mast most likely already has a build-in rail. I have a Beneteau 461 from 1999 with a Z-Fussion mast with a protrusion that goes along the front of the mast. I think that what is considered an integral exterior spinnaker car rail, the wider 3.5" variety (see attached photo; my 'art' is a schematic of what the mast cross section looks like).

Unfortunately, it seems that the cars for that rail are .no longer available from the manufacturer. Does anyone know whether there are any OEM suppliers for these parts? I would rather not drill additional holes and risk puncturing the wiring inside the mast if I could get a fitting car (and whisker pole). I assume the discontinuance of production was not based on the scheme being defective.