about the charms-> we are all probably wondering why we didn't think of that! This is soo cute!! I know I will have to give it a try, as soon as I can get more clay.
about the cereal in Australia-> can you order some from Amazon? I know there is a grocery section there. Here in US we have Malt O Meal brand cereal that does some pretty darn good knock-offs of certain cereal types, and their Marshmallow Mateys are really good, plus they come in giant zip seal bags that last much longer than a regular box. I've done some crafting with the bags, myself, the vinyl pouches, bags...
Lol my mom actually gave me the idea, when i was showing her all the different kind of marshmallows in the cereal she said it looked like polymer clay and so i decided to make them.
It is pretty easy to make since most of them are easy shapes and one colour, the hat and shooting star were the hardest. Maybe make the hat into a cane so the clovers will look like clovers, and the star I have no idea how to make that easier.