A couple things you should think about. In almost any court, a night stick / baton has and will be held to be a deadly weapon. If you use it, you had better be able to back it up with a "use of deadly force defence". To be effective, it will cause injury, so be prepaired for a law suit. It also means you have to be close to your attacker, and dependant on your physical ability and training.
OC (pepper spray) allows you to maintain a distance from your attacker, is NOT considered by the courts to be deadly force, and is very effective if properly used. I have been involved in or witnessed the application of OC in well over 100 incidents, and I can tell you, its a rare man indeed who can continue to function in an effective manor after being sprayed. Use a small law enforcement type fogger spray, put it on target (the face), and you are good to go. I think most OC failures are from people using small, stream type sprays who do not make good contact with the subjects eyes/mouth/nose. Also remember, your not a cop, your not trying to take someone into custody, just get em off you, give yourself an opening to walk away...
A good plan would be a carry gun (I like the Glock 26/27 series), along with a can of spray.
Larry