Valuation for Sam Cooke's version of "Blue Moon" used for An American Werewolf in London

Can anyone help!? I am in possesion of the original vinyl copy of Sam Cooke's "Blue Moon" that was used for An American Werewolf in London. The record was passed on to the mixer and was signed on the back by John Landis. There are interviews given by John Landis to authenticate this. The record was sourced by a record shop in Los Angeles and sent over to London where the post production was carried out. I am interested in finding out the value of it but have had little luck so far. I would appreciate any help and might be looking at selling the record in the near future. Many thanks

, September 27, 2005; 3:51 PM