Sorry Michael.
I bought this lens at a camera shop in Ginza, Tokyo. It is specialized for Nikon and has been around for several decades, so there you can find rarities of Nikon products. I bought it for 5,000 JPY. Even though its barrel is apparently made of high quality brass, and is a specially ordered by someone for some specific use, it was dirt cheap because it is too rare to be a collector's item. Even CRT-Nikkor was like that in the past...