Same thing happened to me. bought a battery from H.K, just needed a cheap one to test an old camera. Never receieved it. Just opened a paypal dispute and got my $4 back the next day.
An important point here. As a prolific user of batteries I find it much simpler and just as inexpensive to buy batteries locally though on-line dealers in Oz. They get to you quickly and you have a telephone number to follow up if necessary. Of course, you still have the possibility of loss in the mail.
The important point is "what items to import". Many of the bigger HK trading companies have established on-shore warehouses in Oz and although GST plays a part in the cost it only represents 1/11th of the price. Often they sell things like batteries from local sources at the same price as their HK outlet.
I only buy small items from overseas when they're not available here.