Miyajima in Japan

I think it's mostly that Miyajima is a very small company, maybe even a one or two man operation, like van den Hul. So as a result they do not produce sufficient numbers of cartridges to provide off the shelf stock for big retailers in Japan. My guess is that was also true of Koetsu.

I travel to Tokyo at least annually to visit our son who lives there. I usually have enough free time to browse the audio salons, and I have never seen Miyajima for off the shelf sale.  However, it is possible that you could place an order and receive a Miyajima cartridge either while you are there or by mail once you’ve returned home. That used to be the case with Koetsu; almost no one carried Koetsu, but the best stores could get them by special order. I bought two Koetsu’s that way and received them in the mail from Japan once we got back home. Complete with factory warranty, by the way. I would check Yodabashi Camera in Akihabara. They have an extensive stock of phono cartridges on display and for over the counter sale.