This is supposed to be the uncut UK version of the film running 5m longer than the various PD dupes of the US version of the film (which is shorter and has alternate footage). It is available for pre-order on Amazon as is the 1967 Amicus SF film The Terrornauts.
There is also an Australian disk out there of Cat Girl which is double-bill withHammer's Shadow of the Cat (no legit DVD release of this one anywhere - Universal have the rights). I am unable to confirm whether this is a legit release at the moment.
There are some interesting double-bills of British films unavailable on UK or US DVD from Australia being offered on Ebay, including the 1968 Linda hayden classic Baby Love, but again it is not clear to me if these are legitimate releases or not. This includes a d/b of Island of Terror (UK version is cut) and The Terrornauts.