The original posts about it are here and here. Jonathan Ferguson, Curator of Firearms for the Royal Armouries, Leeds was kind enough to leave a comment on the followup post pointing to his own discussion of the kit. His take on the authenticity question is worth noting.
Although often claimed to either be made for genuine vampire slayers, or as novelties for travellers to Eastern Europe, this is probably not the case with this piece. I’ve been researching vampire-killing kits for five years, and there is no evidence of their existence prior to 1972, around the time of the famous ‘Hammer’ horror movies. For some people, this makes them ‘fakes’, but is it possible to have a fake if there is no original to copy?
I argue that they are instead ‘invented artefacts’ – movie props without a film. We will be subjecting our kit to some sensitive scientific analysis to see if we can find out more about it, but chances are that it was made relatively recently. This is not a bad thing – museums today collect far more widely than just traditional art and historical pieces, and the level of interest generated by this kit shows how culturally important it is. It’s hard evidence of the undying love people have for supernatural fiction, from Dracula to Twilight and Abraham Lincoln: Vampire Hunter. It also reflects centuries of folklore relating to vampires and the best ways to dispose of them, which for some people, even in the 21st century, remains a frightening reality.
That strikes me as being a reasonable and balanced approach. Vampire hunting kits aren't authentic historical items, but they are objets d'art worthy of appreciation on their own merits. Their value is in the craftsmanship and creativity of their creators. By their very nature they are intended to deceive, but they should never defraud. That's why the use of the word "authentic" bothers me so much.