Founding partner of Walkabout Collaborative, helping independent consultants, professionals and executives build the life and income they want.
There are three sources that I'd recommend for you. First, find your local Startup Grind in the nearest participating city (https://www.startupgrind.com/) - go to an event and network there for a co-founder. Second, take a look at advertising on AngelList (https://angel.co/) for your co-founder. Finally check out the National Venture Capital Association to see if there is a regional group that you can network into for a co-founder (http://nvca.org/ecosystem/regional-groups/). Good luck with your search. Feel free to set up a call if you'd like to brainstorm other solutions.
Take a look at the Expert360 platform at https://expert360.com/
They are based in Australia and seem to have quite a few consultants based in Sydney.