Yes it SHOULD have one.......too easy to over rev these engines.
Its incorporated into the rotor arm. If you take the distributer cap off you'll see the rotor arm is much bigger and has a spring incorporated into it. Centrifugal force throws the spring out and at a given RPM, ignition is cut.
Having said that, it is possible to fit a rotor arm that doesn't have the limiter......just looks like an ordinary rotor arm. So it is possible someone has done that in the past........its cheaper, until you break your engine that is.