If you know a bit on scripting, this isn't too difficult.
Everything about an actor is held in the $game_actors class.
You can access the weapon(s) an actor has with:
$game_actors[n].weapons
You can access the armor(s) an actor has with:
$game_actors[n].armors
Or you can get all the equipment (both weapon(s) and armor(s)) with:
$game_actors[n].equips
replacing 'n' with a number. I'm not entirely sure how the data is stored in $game_actors. I don't know if the actors get sorted into an order, or if they are just added to the end of the array as they are encountered and added to the party. I've not really looked into it much yet. So unless someone comes by to provide more details, just play around with it or run an additional check to find out what actor is at the given 'n' value.
If you want more specific information for Helmets, you can get this from either (in some kind of code format):
armors = $game_actors[n].armors
helmet_id = armors[0] #if using Two Swords Style
or
helmet_id = armors[1] #if not using Two Swords Style
or
equips = $game_actors[n].equips
helmet_id = equips[2]
Obviously, they are stored as IDs so you'll have to find out what armor that relates to. $data_armors[helmet_id] will probably find it though I'm not 100% sure.