Broken or missing luggage wheels can be replaced with parts obtained from the luggage manufacturer, from an independent luggage repair shop, or from vendors such as local hardware stores and Amazon sellers. Appropriate wheels are not always labeled by luggage brand or the specific suitcase model, and sometimes they are marketed for other purposes. For example, wheels advertised for skates might suffice. Measure the diameter of any remaining wheels if possible before starting your search.
You can pay a professional to replace luggage wheels, but the repair process isn't difficult to do on your own. Generally the first step is unzipping the lining of your suitcase to expose the bolts that hold the wheels in place. Then, using a wrench, grip the bolt and turn a screwdriver counter-clockwise to remove the screws that surround the wheel well. A small clip becomes accessible. Push on the clip to remove the old wheel, if applicable. Next, add the replacement wheel and place a washer on each side of the wheel. Secure the new wheel with the clip, and replace the screws. To complete the task, tuck in any loosened fabric and take your suitcase for a test drive to make sure it doesn't wobble.