I found it for region 1 (U.S. and Canada) at Amazon:
Amazon
But, I see you're in the UK. I also found it at the UK version of Amazon but it's still region 1 encoded. (might be it was never encoded to other regions.) You can play it but you'd need either a region 1 or multi-region player, I don't know if you have one but here it is:
AmazonUK
