This is a genuine GM USA remanufactured 9 inch brake booster that fits the 1965 - 66 USA built Impala, Belair.. as well as the Australian / NZ built 65-66 Impala/ Belair and the 65-66 Pontiac Parisienne/ Laurentian series.
Delivery is covered within Australia - but not to Darwin / NT or NW regional remote stations and towns.
This is normally in stock but late 2021 the USA remanufacturers are down & may give up to cheap Chinese imports.
If you prefer to bring one in yourself from the USA the number is 160.80303