Repairable write off meaning the car was insured by an owner who had an accident, big or small, and they wrote it off for him to get fully paid out. It has nothing to do with compliance or registration of the car. It can be registered anywhere (it's already registered now anyway in NSW - the harshest state) - But it's more like a bad driving record for the car to tell people: hey, this car has been in involved in something, check it out properly.
As far as the GTT , nice car and all, but I need cash, urgently!