EDIT: This may be cheap, but for 10p more you can get a genuine Nokia AC-8X Energy Saving charger (small pin). See http://www.hotukdeals.com/item/592045/energy-saving-genuine-nokia-mains-c
Genuine Nokia mains charger (supplied un-packed) for charging up your Nokia mobile phone (using smaller 2mm diameter pin connection). Works with all Worldwide voltages (100~240V) and has a standard UK 3 Pin plug fitted.
There's even 1% Quidco available for the keeners.