Shadowfang Keep

I recently started to twink a level 19 rogue for the battlegrounds and decided to equip him with two Assassin's Blade. Unfortunately several other people had the same idea and the only two available were priced at 400 gold a piece.The dagger drops mostly off the boss mob in Shadowfang Keep, Archmage Arugal. This instance is intended for groups in their low or mid 20's with the mobs ranging from