If you're looking for a dinghy and not interested in class racing, you might consider a Howmar Phantom (not to be confused with the British boat of the same name) if you can find a good used one. We've had loads of fun with ours, and we still sail it even though we've gotten a larger pocket cruiser. They're almost identical to the Sunfish, but with some significant improvements like a seamless cockpit that is much more comfortable to sit in. The improvements (including slightly larger sail area) make it a little faster than a Sunfish, so you probably would not be allowed to race against Sunfishes.
Howmar went out of business years ago, but another company has taken over the design and makes the new ones under the name "Pointer 14," which should make replacement parts much easier to get. J-Point Marine, LLC - Manufacturer of Fine Sailboats