I agree with Sir Taliesin, it's quite useful for a thief or a bard or a ranger. If it's gone, then use shadowkeeper. If you happen to find the scales anyway,
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Go to Cromwell, the dwarf at the docks (far right on the map is his house), it will cost you something but it's worth it.
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I pledged my vows to Torm - Mirac Honorguard (Undead Hunter)