She said the club had inquiries from Russia, the Czech Republic, France, the Netherlands, Germany and the United States of America - "all over the show".
Some were keen to start it up themselves while others just showed an interest, she said.
Mrs Williams said the club had done interviews for the BBC and the Australian Broadcasting Corporation and were featured in an article in the United Kingdom's The Guardian.
Now, a musical-based documentary is being made on the club.
Loading Docs is a documentary initiative, with the support of principal funder New Zealand On Air, along with the New Zealand Film Commission and Te Mangai Paho, which helps fund, create and distribute ten films a year.
The Coffin Club are one of the recipients of this funding from Loading Docs.
They had their first singing rehearsal last week, and the Auckland company came down and recorded it, Mrs Williams said.
"It is so much fun to see these darling oldies singing and dancing."
She said, as far as she knew, the documentary would be made in May and ready for distribution in June.
It's not the first time the club has featured in a documentary, previously being filmed by a Japanese film crew.
"It's been overwhelming but in other ways very satisfying."
Club member Raewynne Latemore said the interest the club had received was "mind blowing" and it was lovely to see others interested in doing the same for themselves.
She said it would be interesting to see what the Auckland film crew came up with for the documentary.
