I cleaned the worst rust with a steel brush. The sanded the anvil with grit 80 to 400 to get the rust away. The best tool for this small anvil was actually a multi tool grinder. I painted the base black with spray paint. 4 coats. Finally I used some steel wool to make it look a bit better too. The cost in this was the sanding paper and paint.
Spray paint • Steel wool • Sanding paper 80 to 400 grit • Steel brush • Multi tool