After spending few hours trying to figure out how to buy the Turkish Ps Plus Deluxe subscription which is about 1/4 of Au pricing, I finally managed to get it.
1) Create a new Psn account (https://www.playstation.com/en-tr/ps-plus/#subscriptions) and select Turkey as the country and use fake address generator to create a Turkish address (https://www.fakeaddresscopy.com/Turkey/). After creating the account go to the (Your information) in setting and edit residential address and add a street address, which is not asked during the account creation.
2) Sign up for a account at (https://wise.com/au/) and add 460 Turkish Lira into the account and you also need to create a Virtual card in the app to pay for the subscription. I tried few different Au bank cards, Revolut and crypto.com virtual card and they all failed for the payment. Edit: $10 fee for physical card, if you don't already have one.
3) To pay for the subscription you actually need to add the card via account management on a ps4 or ps5 console otherwise payment will fail. Also note that when adding the card as a payment method you must use the same Turkish address you used when setting up your PSN account or the process may fail.
4) After adding the card via account management on a console, purchase the ps+ subscription directly from the console for it to work 100%. That's it, enjoy!
And also you can stack the subscription for upto 15 years.
Thanks OP, bought 3 years