Microsoft spares fo optical KBD

> Recently I purchased a Microsoft Wireless Keyboard Elite
> from PC World in Bristol, England. Owing to an accident,
> a few days later, the receiver was thrown away and was
> removed by the dustmen. So, I have a new keyboard and
> mouse which are unusable - an expensive mistake. I need
> a "MS Wireless Optical Desktop Receiver 2.0A", model
> 1012, P/N X09-51906. I would like to buy one, but PC
> World states that they cannot help. The Microsoft UK web
> site has no link to any spares retailers.
> I should be grateful for any leads to a solution.