[Showa Retro] Two High-Quality Miyata Harmonicas - In Box (Includes 2 Bonus Harmonicas)

I found this while cleaning out my parents' house, tucked away deep in an antique case.
After some research, I believe it's a product from the Showa era, supervised by Miyata Toho, as the case is fabric-lined and there's an inscription.
It's likely from around 1975-1985.
Since it's unused, it has high value as a [genuine original Showa retro item].
Although it's new, there are some signs of age-related tarnish and discoloration, so please examine the photos and make your own judgment.
If you purchase this item, I'll also include the two harmonicas shown in photos 18-20 as a bonus.
These two bonus harmonicas were stored in the same location, but I cannot confirm if they are Miyata products, and they do not appear to be new, so please be aware of this.
As this is a musical instrument, I have not tested it by playing it, and I do not accept returns. Therefore, please only purchase if you understand and accept these conditions.
This is recommended for those who collect Showa retro goods.

Thank you for looking.