Because you are in Australia, you have to check out your local australian suppliers. Korea and Japan are your nearest countries which have 18650 factories.
best way to use google in Oz:
https://www.google.fr/search?num=100&ei=vVruWpT8NMOS6ASuhaCYBg&q=18650+site%3Aau&oq=18650+site%3Aau&gs_l=psy-ab.3...13172.13938.0.14164.5.5.0.0.0.0.171.596.1j4.5.0....0...1.1.64.psy-ab..2.0.0....0.uIpMJWwLVi0
Oz 18650 topic:
https://www.ozbargain.com.au/node/324863
to ship from europe, you can check out the for sale zone of this forum. If you get from ali express, weigh the batteries and use the guarantees if necessary: https://fr.aliexpress.com/item/Useful-2-4-8-12-16-20PCS-3-7V-NCR-18650B-3400mAh-Rechargeable-Batteries-For-Panasonic/32833159302.html?spm=a2g0w.search0104.3.1.489415a8kbzhTk&ws_ab_test=searchweb0_0,searchweb201602_1_10152_10065_10151_10344_10068_10342_10325_10343_10546_10340_5722611_10548_10341_10698_10696_5722911_5722811_10084_5722711_10083_10618_10305_10304_10307_5711211_10059_308_100031_10103_10624_10623_10622_10621_10620_5711311_5722511,searchweb201603_32,ppcSwitch_4&algo_expid=0c9f82e9-2372-4fba-8ee2-3658503aa525-0&algo_pvid=0c9f82e9-2372-4fba-8ee2-3658503aa525&transAbTest=ae803_1&priceBeautifyAB=0