lovely watch -and I agree that it's not very common -there aren't too many Tissot chronometres about.
I too have an early 70's seastar that I inherited -very similar to Canberra's.
I posted it on WUS and it led to me to research the connection with Omega -it has the 2481 sister movement to the Omega 1481.
There are some knowledgable guys on there that might help.
I began looking for a Tissot Chronomter just like yours which led me to the Omega Constellation I now have.
here is some info I found whilst researching the Tissot Chronometre that might help
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My Tissot says hi.
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