Brian, I have a vintage flyer somewhere from this firm, I will post it when I find it.
They started working for the movie-companies in Japan. The interest for the samurai increased in the seventies and eighties, more and more people wanted a kind of 'relic' from this culture.
Some of those movie prop katchushi were really good, and became famous.,
One of them, Ototsugu, was even listed in Sasama's Shin Katchushi Meikan.
His work is sold for millions of Yen nowadays.