A very small and cheap 2.4GHz USB wireless adapter on flash sale from Comfast. It uses the MT7601 chipset and has an inbuilt antenna. I keep a few budget adapters in my toolkit for those sticky situations.
Alternatively you can get an unbranded one here for only US$1.87 (~A$2.58) with the same chipset if you're not concerned with brand and potentially a better product.
AU$ based on current Mastercard rate, GST inclusive and stackable with cashback.