There is also a small scale producer that is not listed in the article: Kakimori (Tokyo). https://kakimori.com/english https://kakimori.com/english I own one

There is also a small scale producer that is not listed in the article: Kakimori (Tokyo). https://kakimori.com/english https://kakimori.com/english I own one of their ink pens but I use it rarely so I can't say much about durability.