I have a buyer for a jersey and it needs to go to Australia. Has anybody shipped there before? If so, what is the most cost effective way to do it? The buyer said they were shipped a jersey recently via "USPS International First Class" for $18.

Am I doing something incorrect here—it normally costs me $12-15 just to get it across the US. It can't possibly get there for only $18 (I don't want to wreck the jersey by stuffing it into a tiny package)...

The online USPS calculator appears to only do Global Priority which is about $60 and my local PO was less than helpful. FedEx was insanely expensive.

Any tips?