Sorry to revive an old thread but I am in a similar situation.
My post office says they cant make an international money order to the U.K. They said that they thought a normal Postal Money Order would do (although they seemed quite clueless).
So anyways, i bought one and it states on it "Negotiable only in the U.S. and possessions"
I emailed attitute 2 days ago asking if they would accept it, but i have not heard back from them yet.
Anyone here ever had this problem, or know anything about this?
Any help would be greatly appreciated