By a ball, do you mean a runabout ball? If so, their nickname is "death ball" with good reason. They are totally unsafe for a chinchilla. Chins don't run, they hop, and the heat and humidity in the ball when they are closed up can be deadly.
Most pet owners have wheels for their chins and the chins really enjoy it, especially those who don't get as much outside of the cage time as the owner would want.
For other ideas, check the classified section here. There are all kinds of different advertisers with toys, loofah, hammocks, etc., to make life more fun for your chin.