FYI they did sell the Volt in Australia as the Holden Volt between 2012 and 2015, they only sold 246 in that whole time though, so not a lot of choice out there on the second hand market.
The closest thing in a new car will probably be the Mazda MX30 R.EV hybrid coming to Australia in 2024, which is primarily electric drivetrain but uses a small petrol rotary engine to charger batteries as a range extender, but that is a very niche vehicle and the rotary engine isn't particularly fuel efficient on petrol use, but it is small and lightweight compared to a piston engine.
Nissans Qashqai and X-Trail hybrids also use a primarily electric drivetrain with the petrol motor only providing power to the electric drivetrain, similar but not quite the same thing as the motor is in use a lot of the time.
The closest thing in a new car will probably be the Mazda MX30 R.EV hybrid coming to Australia in 2024, which is primarily electric drivetrain but uses a small petrol rotary engine to charger batteries as a range extender, but that is a very niche vehicle and the rotary engine isn't particularly fuel efficient on petrol use, but it is small and lightweight compared to a piston engine.
Nissans Qashqai and X-Trail hybrids also use a primarily electric drivetrain with the petrol motor only providing power to the electric drivetrain, similar but not quite the same thing as the motor is in use a lot of the time.