Thanks to Big Paddy who shared this tip in the T-Mobile deal.
Free 15-day trial of the full Visible plan (on the Verizon network), including unlimited 5G data (inc 5Mbps tethering, one device only), unlimited talk and text with the US. Doesn't require a credit card etc, apparently quite easy to activate.
If you are in the US for a longer time, you might be better off with the T-Mobile deal (which gives you three months of service). However, that deal doesn't include calls, texts, or tethering (and possibly throttles video to SD), so for a shorter trip this one is pretty appealing!
FAQ about the Visible deal here: https://www.visible.com/help/free-trial
Unlikely any Australian phones will be compatible. Verizon uses the CDMA network which no aust phone will support.
Enter your imei below to check compatibility:
https://www.visible.com/shop/compatibility