The Sorrows adorned outfit consists of a simple loincloth for males, with an additional sports bra-style top for females. It is decorated with necklaces, an ankle band, and an armband with two small feathers.
Zion Canyon - Worn by some members of the Sorrows tribe. Openly killing a Sorrows tribal to acquire the outfit will immediately fail all associated quests in Zion and initiate Chaos in Zion. An undetected sneak attack will not affect any quests.
White Bird's cave - Worn by White Bird. It can be obtained by pickpocketing him and placing armor with a DT higher than 2 into his inventory. Exiting the cave, traveling elsewhere and then re-entering (thereby initiating a loading screen) should cause him to equip the higher DT armor. The Sorrows adorned outfit can now be pickpocketed from him, causing Karma loss but no quest failures.
Three Marys - This armor, along with a Dead Horses stalker armor, may be found at the White Legs camp. Directly under the map marker the river flows around a small island, on which two slain tribals are lying - a Dead Horse and a Sorrow. The Sorrow will be wearing either this outfit or a Sorrows outfit. Their armor can be taken without penalty or risk of failing any quests.
Their appearance is triggered by your first meeting with Joshua Graham in the Angel cave. Traveling to Three Marys after this should cause the bodies to spawn.