Hi Canagirl, as far as I understand, IVIG, steroids and other immunological treatments can help SFN only when it is cause by immunological disorders. All of these treatments got serious side effects and some of them are also very expensive.

I can highly relate to your pain and despair but from my long experience with doctors it seems very few of them would be ready to listen to suggestion based on the internet, not to mention, read papers.

I suppose the best chance would be to try convincing your doc to try a short term usage of prednisone. If it would help it might easier to justify other immunological treatments.
This paper might help you convince your GP
Dabby et al 2006, Acute steroid responsive small-fiber sensory neuropathy: a newentity?
http://www.ncbi.nlm.nih.gov/pubmed/16519781

Do you know how to search google scholar for papers ? http://scholar.google.com
At the bottom of each item you can find a link to all of the versions that were found, pressing on it would open a list of locations, some of them might be free.

If you find relevant abstracts and can’t access the full text, PM me with the links of the abstracts and I might be able to access the papers.