Welcome and Shanolom Aleychem. Not sure what is available in Australia, but you are corect there is plenty of kosher stuff here. I have plenty of recipes that are adopted for kosher. Will be happy to answer any questions.
Don't know what Sydney is like, but the Jewish population in Perth pretty much used to live in a couple of central suburbs and there are several shops that cater for Jewish cuisine/traditions in those localities. Likewise, more likely to find those items in the national supermarkets within those suburbs too. Try a similar approach in Sydney.
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