Interestingly the idea of vampires is know by many cultures ...albeit with slightly differing descriptions. It seems that there was a genuine scare in Eastern Europe in the 18th C, that vampires were 'everywhere', bearing in mind the lack of education and the superstitions that pervaded society at that time, it is easy to see why every 'unusual' death (including animals) was 'the work of a vampire'.
So conceivably the 'well to do' could have indeed 'comissioned' the manufacture of 'Vampire killing kits'. Although it is likely the 'kit' that started the thread is 'spawned' from the popularity of Bram Stoker's book....early merchandising?
Also, some of these so called kits have a firearm and silver bullets...I cannot find any reference (pre-dating Stoker's book) that mentions their use against vampires....definately suggests that these are 'made up'.
Surely a crossbow would have been better....to shoot your Hawthorn (the best wood to use) stakes....from a distance or.... an Uzi with 'wood-tipped' bullets