Configure Australian GST Taxes on Commerce Kickstart 7.x-2.14
Here is a module maybe is useful.


  The Commerce Australia module provides a number of customisations for
  Drupal Commerce (http://drupal.org/project/commerce) that allow it to
  be better suited for deployment in Australia.
  
  Most notably, these include basic currency formatting for Australia
  and workable GST (Goods and Services Tax) rules.


https://www.drupal.org/project/commerce_australia