Well, this is surprising. So I went to Japan shortly after this and was able to work as a kurabito for part of my stay. When I returned, my hobbies went elsewhere and I did not continue homebrewing sake. I may still have the koji from Akita Konno, I'm 90% sure the bag was never opened. It may take me a few days to a week to track this down when I have the time. If I find it, I'd be willing to sell it as-is. It is a 70gram bag, suitable for 200kg of rice.
As for how I was able to get the koji, I sent an email to firstname.lastname@example.org. One of their employees replied in English with a price sheet. They do accept international orders via wire, I have a family member in japan that helped me with a domestic order, for a lower price.