I got my pair from National Animal Welfare Trust and they cost me £60 each to cover the worming, anti-flea treatment, neutering and microchipping.
Best £120 I ever spent!
One of mine chewed through the wire on a phone charger whilst it was live (on the 12v DC side luckily) but doesn't seem to have suffered any ill effects and hasn't been quite so keen to nibble on wires again.
For anyone feeling the need for feline : The Cat Rescue Resource - covers most of the UK & parts of Ireland. There are even rescue centres that specialise in pedigree breeds not just common moggies.