Yes, replacement limescale filters for Dualit kettles are available by contacting Dualit Customer Service on 01293 652500 (UK delivery only). When ordreing a new filter please have the kettle model and serial number to hand (shown on the base).
The heating element of a Dualit kettle is sealed within the unit and is not therefore replaceable. Please contact Dualit Customer Service on 01293 652500 (UK customers only) if you are experiencing problems with your kettle.
Your kettle cannot rust as the main body is made from stainless steel. However, in some areas where the water contains a high quantity of iron oxide, the natural limescale deposit inside your kettle can become tainted brown or black. We would therefore suggest that you try de-scaling your kettle with a good quality de-scaling product; this should remove any staining.