One thing to consider is a stout walking stick or something like that. Nothing too obvious, but strong enough to be used as a self-defense weapon.

Somewhere in a recent post, someone had a link to an "unbreakable" umbrella (sorry I can't find the link at the moment). Consider something like that.

There you are walking along with your quaint stick or umbrella; no one would think you have a weapon in you hand.

Just a thought...