I'm guessing you are talking about air shipping and not through the post office, right?
I would call the airport and find out. When I was looking to ship my cats from Guam to the states, it was around $600 per cat. But, there was no quarantine going back to the states, but I'm guessing going from one country to another they would have their own regulations and quarantine fees.
I think what every airport you are booking through should have info on the international requirements.