This lens is very rare. It took me a long time to track one down, and that was only possible with the help of Xavier, a very friendly guy from Spain who also uses Mamiya NC cameras.
I think this lens is so hard to find since the Mamiya NC cameras were usually sold together with a standard lens, and only very few people were willing to spend the extra money on a macro lens with the same focal length as the standard lens. This macro lens was also one of the more expensive lenses back then (around US$ 200).
The lens focuses down to a maximum magnification of 1:2. There is also an extension tube “Macro CS” available for this lens for 1:1 magnification.