The part numbers from digikey.com for the buttons and their caps are on the bottom of the blog post. You will need to see if the distributor digikey does business in Australia. I only have enough for my two prototypes and a few extra. I first tried to but some off ebay and I got 100 of them with caps. Too bad they are not tall enough even for 16X2 displays. Can't find the link but if you see something on ebay and want me to look at them just post the link.