Listed here are links to 15 cajon makers in Japan.

YouTube playlist of cajons made in Japan:
Note that not all manufacturers have current YouTube videos. The list on this page includes websites and Facebook pages which may contain videos not on YouTube. It is current and is actively maintained. The YouTube playlist is infrequently updated.

One photo per Japanese cajon manufacturer in Pinterest:

If you are a native Japanese speaker, please help me improve this page. I would like to use: "Cajon Drums Made in Japan" in Japanese as the title. I would also like to have each cajon manufacturers brand name in Japanese. For example Koshikari Cajon (越仮カホン). I am not sure if this is correct. And I would also like the other names in Japanese. Also, it was difficult for me to evaluate these sites. Perhaps I got the manufacturer wrong. Any input would be greatly appreciated! Thank you!

These links to the cajon drum builders in Japan were retrieved by Internet searches in March to July of 2018. I am sure there are other Japanese cajon makers not listed. Please send me updates and correction if you have additional information. Thanks.