Escadrille, I checked mine and Henk's yesterday. He has 24046 - single pole (no separate earth but still insulated) and I have 24047.
I also noticed that Cole Hershee is a USA company, not German (not that there's anything wrong with that).
I got mine through City Centre Auto Electrical in Canberra. Any Auto Electrician should be able to get it though. Lucas or Bosch would also have something which would do the job better than standard. I couldn't find a price. Probably $80ish.
The crux of it is that the cheap unit leaks current to earth. As it warms up, it leaks more. So after 5-10 seconds of cranking, it seems that the battery is out of grunt and won't turn the engine over anymore, when in reality, there's plenty left, it's just going into warming the earth return. I guess if you ran the earth near the carby it might help to warm things up (or light them up), but I think you're better off with a quality solenoid.
I would really like a few more Jab owners to try this and report their findings. I'm confident it would end the Jab jumpstart jamboree we see on cold mornings at fly-ins.
Cheers,
Ross