I guess it's a typo on your part. You used "@actor" instead of just "actor".
Next, this:
$data_armors[actor.armor3_id].icon_name
unless actor.armor3_id != nilshoud be this:
$data_armors[actor.armor3_id].icon_name
unless actor.armor3_id == nilNice idea btw, I'm thinking of adding this in my game
EDIT: Oh, forgot to mention the most important thing, it's not
$data_armors[actor.armor3_id].
nameits
$data_armors[actor.armor3_id].
icon_name