Both black and silver are available - silver here: https://store.sony.com.au/headphones-noisecancelling/WH1000X...
The Sony WH-1000XM5 hit the local market on 14 June and I've been keeping an eye out for a great deal, after I picked up the previous generation WH-1000XM4 for only $351 shortly after its release, in 2020 (thanks Ozbargain - https://www.ozbargain.com.au/node/558941).
Whilst not as epic as that deal, I worked out that with Cash Rewards' 10% cashback offer on Sony Store Australia Online purchases (EDIT - seems that Sony don't include the GST within the cashback calculation), it brings the price down to $498.09 (once you receive the cashback in your Cash Rewards account).
The deal becomes much more attractive if you have an American Express issued credit card as once you log in to your Amex portal and enrol in the offer, you will receive $75 credit back to your Amex, upon spending $500 or more. This is a targeted offer but whenever someone posts these offers on Ebay, my Amex always seems to have them as an offer I can 'save to card'. https://www.ozbargain.com.au/node/699629
After the receiving the $75 cashback to your Amex, you've picked up the awesome new WH-1000XM5 for only $423.09 delivered. The $75 cashback from Amex expires tomorrow so be quick.
Mod: Prices in title should not include post-cashback pricing.