All the parts are readily available for these carts. Bike America in Kansas has a large inventory of parts for the Sharp Mini T's, and the original McDonough Tin Lizzies. The 800 number no longer works. Call 913-381-5431 ask for Gary in the Sharp Mini Car Division. They are very freindly, and very helpful.
If you need a parts brochure, I have them from James Mini Car Company (they bought out McDonough), and can email them to you.