Hi Kaye,
indeed to IIS.
The two clubs below are great options. In this particular forum you will also find other informal gatherings which I'm sure you'll be able to hitch a ride with someone to attend
Between which dates will you be in Sydney? This will help us give you the best information. Where abouts will you be staying in Sydney? This too will help. I'm in Sydney's east, not too far from the Airport to give you a reference. Getting a car or need a lift?
Cheers,
Alex.