Shipping costs to Australia vary based on the courier used and the weight of the ordered products. See here for detailed shipping costs.
On Oliunìd you can always return a product excluding customised products (e.g. lanyards cut to the metre, kits assembled by us, etc.) for any reason: it's not what you expected, you got the wrong shoe size, you don't like the colour of the trousers. You have 100 days to do so. Read the full policy here.