If you’re using rubber knives or foam sticks, to plastic knives and real wooden kali sticks, and planning on aiming for the head, a fencing helmet will offer you maximum protection. I don’t advise using regular headgear. That kind of stuff doesn’t protect you from a stick strike very well. Nor does the front of the headgear which is completely open protect you from a knife strike.
Bottom line: For any sort of weapons sparring involving knives (Never real knives!) or sticking fighting, use a fencing helmet. You’ll be glad you did, I promise.
Recommended suppliments for fencing helmet:
Rubber knife (for sparring).
Shin guards (to protect your legs).