Great project!
There was an interesting discussion about a similar kit in the Survival Arts forum (which no longer exists, but
here's a link to the wayback machined thread), when one sold several years ago. A guy named Michael De Winter claimed to have invented the Vampire Killing kit in the early 70s, when he was in the antique guns trade in London. One day, a customer traded him a low-grade Belgian percussion pistol as part of a deal, and figuring it wasn't worth anything else, De Winter fobbed up a "Vampire Killing Kit" as a Barnum stunt, and priced it outrageously for its advertisement value. Then he started seeing copies of it pop up, all of them copying the original bunkum text he'd written.
That was De Winter's story, anyway. I'm inclined to believe him, as pre-Dracula vampire lore is all over the place, and if you look at the contents, the stuff that got packed into these supposedly historic kits is all the kind of thing that somebody would pack if they'd seen a lot of Universal horror movies.
It's a terrific project, anyway.