I saw a copy in the archaeology section of my local library the other day - might be worth a try to keep you going while Waterstones get hold of it, if they can. It would be interesting know how much the retail price of a new copy is.
As if by magic:
http://cgi.ebay.co.uk/Julian-Cope-The-Modern-Antiquarian_W0QQitemZ280310334352QQcmdZViewItemQQptZUK_Books_NonFictionBooks_NonFictionBooks_SM?hash=item280310334352&_trksid=p3286.c0.m14&_trkparms=72%3A1687%7C66%3A2%7C65%3A12%7C39%3A1%7C240%3A1318