Tourmaline is not a australian gem... You have unique opals, it's enough
...
I have found for you an indian shop, with several sellers for "melon d'eau" tourmalines and other, somes are drilled as pearls, not expensive:
https://dir.indiamart.com/impcat/watermelon-tourmaline-gemstone.html?biz=20
For tourmaline faceted pearls :
https://www.gemselect.com/french/group/gemselect.php?a=0&g_type=85&drilled=Drilled,Half-Drilled
To buy blue tourmalines, all coming from Brazil, you can search on Google "Indicolite (or paraïba) tourmalines", you will find gorgeous gems, but not for my purse !!
Maybe Lady_Disdain, member of this site and living in Brazil, will know better plans than mine.