My LAME rang around operators and distributors here in OZ and came up with carnuba automotive wax.
Be careful. Very few automotive waxes these days are primarily carnuba. Most of those with some carnuba also have cleaners of some sort in the wax. It is my impression that real carnuba wax tends to be very stiff as well and may need some heat to soften to wear it is workable.
You can get the real carnuba wax, but you have to look for it. Best bet would probably be an outfit that sells to the high-end collector or detailer.