You'd probably be better have been placing this in the Australian forum.
Think last quote I'd seen posted on one of the local FB forums for a RWD was about A$18k, but don't think I've seen any reports of replacements out of warranty (and even that is a very small number of early failures).
There's a 2021 3 (so LFP made in China) in Brisbane that's mostly used for Uber that is already over 290,000km travelled. Still on original brakes and battery.
Most regularly driven 3s are still well within battery warranty, and only a small percentage of Australian 3s are outside the 4yr main warranty.