The armored car is an Alvis Saladin, armed with a 76mm L/23 gun.
During the Vietnam War, the Australian army took a Saladin turret and grafted it bodily onto the hull of the US M113 APC, turning the latter into a fairly effective light tank. This was called FSV (fire support vehicle) officially, but the soldiers always referred to it as “the Beast.” Similar vehicles, with the same gun but the lighter and more modern Scorpion turret, are still in service today.