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.