It's funny ... I had a similar situation...

The very last international customer I did take 
asked ahead of time if he could bid.  I was 
desperately in need of the money so I said yes 
and quoted him the shipping costs for Airmail and 
EMS shipping.  I also told him that if he didn't 
want to pay those shipping costs then do NOT 
bid.  He bid and won the auction.  When he sent 
the money, it was an amount somewhere between 
Airmail and EMS.  Yet he insisted I ship EMS.  I 
contact ebay and apparently he contact his ebay 
in Germany.  Mine supported me, his supported 
him.  That's when he started getting more 
forceful and threatening.  That's when I decided 
that I would no longer take international 
customers, overseas or Canada.