A company that will replace broken drapery cord?

My parents have the old style drapery track, that their main living room curtains are on, they are pulled open and closed by the cord on the side of the drapes.The cord has broken. Does anyone know of a place that will come in to replace the the cord system, as it has broken because of age I am sure, and I am not about to tackle this myself. It is quite a large picture window too, with fairly heavy drapes.
They are in the Etobicoke, Ontario area.
thank you.