S&J automotive in Edwardstown will do an Ekutek flash, was quoted $1400 for an initial tune then $700 for any retunes. Have been really impressed by their techs so far.
I'm not aware of any Subaru focused Haltech tuners around adelaide, but there are a few Haltech partners you can find on their website
https://www.haltech.com/dealer-list/?reg=au#4552576