Some while ago we had advice from eBay as what to do from foreign parts. Another member copied it out - I have it somewhere and will quote them if I can find it ["Oh ha ha"].
This was - basically - just proceed as normal. Simply open the case for "Not as described" [etc]. When seller does not send label after 3 days simply escalate to eBay who will deal with it. Foreign seller certainly "could" buy labels from RM if not through eBay.
@lilacbel2005