I’ve bought this case (RRP $69.95) for my iPhone 15 plus and fits like a glove. There’s apparently slight differences in dimensions but all the parts align and the buttons work.
I believe most other cases for the 14 plus will work as well. There are a lot reduced at JB atm. A lot of them are free if you have use $10 JB Hi-fi perks codes.
Also bought this wallet type one for $3 at Officeworks, don’t like it as much although the wallet and the case can be separated. https://www.officeworks.com.au/shop/officeworks/p/otto-textu…
There are also a lot of reduced iPhone 14 Plus cases at Officeworks. Picked up an Apple and an Otterbox case from another post for $9 each.