If you are planning on pulling it a bunch and don't have a spare, I'd buy a new set of wheels and tires. Then, you can clean the old ones up and use one or both for a spare.
If you're not pulling it much, I'd take them off, clean them up as much as possible and spray them with your choice of color in a spray paint with rust inhibitors in it. You can even leave the tires on them. Coat the sidewalls of the tire with Crisco or something similar that will keep the paint from sticking to the rubber. Paint the wheels. After the paint is dry, take them to a car wash and blast the sidewalls clean.