USB WiFi dongle

Does anyone have any recommendations for small USB WiFi dongles? I don't care too much about speed for this use case - mainly about price and size.

I already have WiFi onboard my router, but I need to be able to add a second connection for this particular use case.

It needs to support client mode, and it would be good if it could support AP mode too, but that isn't strictly necessary.

Also would be good if it's available in Australia.

Thanks in advance!