hi there numbfoot, I am a fellow kiwi
Personally I have found the treatment in NZ for PN is pretty good - I have had all the testing I need in terms of nerve conduction studies, emgs etc, which I am sure you have had too. I have sensorimotor axonal neuropathy, meaning that if effects both sensation (numbness) and motor function.
It just depends on how aggressively you want to search for a cause - but one thing that I can absolutely guarentee is that knowing the cause doesn't necessarily make the treatment for the neuropathy any better. I have lupus, which causes my neuropathy, I have absolutely A grade treatment for my lupus but it does absolutely nothing for my neuropathy. My neuropathy still progresses despite treating the cause, go figure.
What your progression will be is one of those unanswerable questions - there is just no way of knowing.
I won't repeat my story here, it is rather a lenghty one, but if you search under my name you will find it easily.
What part of NZ are you in ? I am in Auckland
cheers
raglet