In a recent hotfix, Blizzard brought back the original vendors from Korrak's Revenge. These vendor sell Timewarped versions of Alterac Valley items, including some previously removed apperances.
To purchase these items, you must visit your factions vendor outside of the original Alterac Valley entrance, in Hillsbrad Foothills. For Alliance, you can find Time-Displaced Thanthaldis Snowgleam at 44.74, 46.46.
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