Nilfisk and Electrolux Panther GD930/S2 commercial vacuum cleaner top cover latch.
As it's light, maximise the saving on postage and buy some of the related parts below, such as 15 litre paper dustbags and the foam dust filter or new hose Pn 140-2782-500 or a new floor tool.
At the moment, standard postage within Australia is capped at a maximum of $25!