I always do that on Yahoo Japan : Yahoo put the 
"seller don't ship internationaly" by default so 
even people who would agree usualy have it 
selected. (And I don't see what's the problem of 
sending to another country if the buyer accept all 
the term of the seller. With the number of people 
that wait a couple of weeks before sending money, 
I am pretty sure that if an international buyer 
send the money immediatly, you will receive it as 
quickly as most local buyers)

Cheers,
Yann Stettler