The older Luxeon K2 LED emitter seems to give better overall colour accuracy than the latest Crees (which are more power efficient but can be to high a colour temperature).

If you need a replacement then I would try one of these in a conventional desklamp.

http://www.dealextreme.com/details.dx/sku.15734

Many LED desklamps are pretty horrible. At least if you don't like the K2 LED you can replace it with a conventional tungsten filament bulb.