Just like to add that Citisuper near Woolworths town hall is probably one of the best stocked Asian supermarkets, I found powdered agar there for $1.39 or something per 25g way better than any of the online resources.
They also have things like acetic acid, maltose and a lot of other random ingredients, also Thai Kee on Cambpell St have powdered lime which may be able to replace the lye in some of the recipes. Maybe somebody else can confirm?