In Australia, I am sure there are Union choirs still ....

When I lived in Darwin, NT, during the 80-90s, there was a Community Performance Choir celebration every May Day, which I was in a number of times.
Once I moved to Queensland in the 90s, I know there were similar choirs in Brisbane. Whether or not they are still going, I am not sure; I'm a bit out of the loop!

I'd be VERY surprised if Sydney wasn't represented though!

Cheers,
R-J