This is 1957 Cooper T43 with chassis number F2.28.57. It was brought to Australia in 1957 by the Australian Gold Star Champion, Alex Mildren.
In Mildren's hands, and with a 2-liter Coventry Climax Motor, the car was very successful in Australia including winning the prestigious Lowood Trophy for Formula One cars.
The car was driven at the opening of the Australian Grand Prix at Albert Park in Melbourne in 1995 by Stirling Moss and still retains its Rob Walker livery.