A car charger (or EVSE, Electric Vehicle Supply Equipment) should be installed by a licensed installer, who complies with AS/NZ3000 wiring regulations.
Here are a few national companies that work with local installation partners, in no particular order:
EVSE
JetCharge
Evolution
Platinum Electricians
or your local licensed electrician.
Expect to pay about $700-$1200 for the charger (tethered/untethered, 7kW-11kW-22kW),
and $700-$1500 for the installation depending on the complexity.
For example: EO Mini Charger and installation by EVSE.