Standing lamp potentiometer broken

I have a nice floor lamp at home that has the potentiometers circuit broken (I checked the fuses already) does anyone know if these potentiometers are standard? Where can I buy a new one to fix my lamp?

Details about the make and model here: http://amzn.eu/d/ftMo7vc .

It uses halogen bulbs which explain that the potentiometer is rated at 300W which is absourdely large and inefficient. If I had a way to upgrade the lamp to an LED light bulb I would have a go with it, although I am afraid that will overcomplicate things.

Thanks Vasilis. I realise now that my question is missleading. I was referring to the complete electronic package as a whole, including the dimmer and the electronic transformer. I tried to find it in Rapid Online without success. I image the package is too specific to be bought. Unfortunately I do not have the tools or the skills to identify exactly where is the fault.