are replacement parts expensive ?

It's rare for a resistor to fail spontaneously - the usual case for a burnt out resistor is some other component failing - a short perhaps - a resistor in the same circuit then has to take more current than it's designed to take - and it burns out. Your burnt out resistor may well be a symptom of another fault rather than the fault itself.

As for the cost of repair - a good tool shop may be able to advise.

Peccavi
May 2011