they do them new from Chet at ricambifiat500 or Franco at Ricambio, normally they have listings of them on e bay.
Another possibility of course is 126fan.sk
126fan might be cheaper but the locals will probably get it to you quicker.
Normally with me it's a panic to get the bits as my 126 is my only set of personal wheel other than bikes which the wife gets grumpy about in winter.
