Wait until it arrives.
Confirm your suspicions
Contact the seller.
Ask for your money back. Mention that it is illegal to send counterfeit items through the mail.
If he does not refund you, go to the Resolution Centre at the bottom of this page and open an Item Not As Described dispute.
Step one is to contact the seller.
You will have done that.
Make it clear that the item is counterfeit and that it is illegal to mail it, so it cannot be returned to the seller.
In most cases eBay and Paypal will require the return and with Confirmation of Delivery. Since this costs over $40 to China, you don't want to do this.