I've just checked worldwide postal prices, and the costs are as follows;
UK, postage FREE
Airmail to Zone One, which includes the USA is £2 extra, so £5 in total for a copy bound to America.
Airmail to Zone Two, which seems to be everywhere else, is £2.50 extra, making £5.50 in total.
American views please note; the Museum of disABILITY History, of Buffalo, New York, had twenty copies from me to sell themselves. They may still have some left if an enquiery is made. Of couse copies can always be purchased direct from me no matter where in the world it is to go to......