My daughter replied to GRAND ILLUSIONS YouTube "Cumos Boxes-or Cosmos in a Box".

Cumos Boxes - or Cosmos in a Box のメッセージへの返信

" Thank you for the fantastic review! I am a daughter of Minori Yamazaki. He has all the materials to make new boxes but in spite of the simple structure, it takes time to make each one. I just want to let you know that he has always wanted to make them available but he couldn't fully focus on it because he had to raise 3 girls including me and work as a professor at an art University at the same time. He just retired his job this spring but has been busy handing over his jobs these few months. (expecially in terms of the covid-19 situation he had to organize some online class for the school.) Hopefully he could share some updates soon! He is more active on facebook than any other SNS so please follow him! mostly it's in Japanese but you can see some recent activity like doing workshops etc. "