Dungeon Siege Revived/OC Helmets
OC helmets always appear as the third hairstyle type (short hair) when equipped by an elfgirl. This is just because there are so many helmets adapted from the original game that it is a mind boggling amount of work to make another 112 models for the other hairstyles right now.
In order to see the inventory icons for these helmets and use them with other player characters (farmgirl, farmboy, dwarf, skeleton, drake, or gargoyle), you need to have either Dungeon Siege Revived or OC Helms Pack #1 installed (the latter does not add the helmet meshes for drake or gargoyle).
helmets oc_ancient, oc_ancient_spikey, oc_mag_wing, oc_ritual, oc_spikey