A friend of mine accidentally lost hers throughout organization of her inventory and I feel like in this instance it should be re-obtainable if the quest is still open and the pages are gathered, but the npc will only give you one, even if you no longer have one in your possession. Somehow I feel like a crappy piece of armor would not hurt anyone to be repeatable, seeing as it is just a fashion item to tell people you participated in the halloween event. Please do this for us Anet, it is a minor change with like no drawbacks…