Hello,
I have a set of Nikon-mount Zörk Multi Focus System with an EL-Nikkor 150mm f/5.6 lens for sale. I can throw in a couple of 3rd party extension rings free (they need to be exchanged for ones with proper internal lining).
$500 OBO. More info:
http://www.zoerk.com/pages/p_mfs.htmYou can check my 100% positive feedback on the auction site by checking mikolaj-i.