Thanks for the update David.
Electoral Registers 2003-2005 show a Kathleen McCaskell living in Balloch (an internet search shows this is at the north end of Vale of Leven). This would fit with the 2005 death Annette found.
I have the full address but I'm not sure if I should post it in case this is not our Kathleen and the lady at this address is still alive. (pm me if anyone wants the full address).
Added: Just found another Electoral Register for another female McCaskell with a birth date around 1948-1950 at the same address in 2003 and 2004-2007.
