Riverside Centre, Brisbane and QV1, Perth

https://skyscraperpage.com/cities/?buildingID=1097 40floors, 466ft 

https://en.wikipedia.org/wiki/Riverside_Centre,_Brisbane "Completed in 1986, it contains 40 storeys and rises 146 metres (479 ft) above ground." https://skyscraperpage.com/diagrams/?cityID=170&searchname=timeline , https://skyscraperpage.com/diagrams/?cityID=170&status=15

Brisbane and Perth have a similar looking office tower.

https://en.wikipedia.org/wiki/QV1 "QV1 is a 40-storey modernist skyscraper in Perth, Western Australia. Completed in 1991, the 163-metre (535 ft)..."

https://skyscraperpage.com/cities/?buildingID=1263 40 floors, 533ft https://skyscraperpage.com/diagrams/?cityID=168&searchname=timeline 

The big question is, will WA ever permit some Gold Coast size resedential towers? https://skyscraperpage.com/diagrams/?cityID=712&status=15

https://skyscraperpage.com/diagrams/?stateID=51&status=15

https://www.quora.com/Why-doesn-t-Australia-build-up-the-west-coast-north-of-Perth-with-resorts-as-in-Queensland-It-could-bring-in-people-from-the-UK-to-help-develop-it-then-settle-there-afterwards

While cold Canada has a lot more towns that could gradually be expanded into proper cities, the warm coast of WA has tremendous potential for urban growth. Yet, most of the state can or will likely remain undeveloped. 

https://www.reddit.com/r/WesternAustralia/comments/19azez6/is_there_a_reason_why_there_are_so_few_cities_on/