I ordered it straight from the company: Link to the Fisch site.BTW, Tacitus.....I never heard of that Fisch before. Interesting, but it's a pricy little gadget for what it is. Where did you get yours?
It is expensive, and it took me awhile to decide to spend the cash. I tried to save some money by only buying the testers for AGE/Krugerrands, US pre-1933 Eagles and Double Eagles, and Sovereigns (Wallets 2 and 3). I also bought the Ringer, because apparently the best tungsten counterfeits can be pretty good, but if you get a good high pitched ring, you are good to go.
In hindsight, I kind of wish I'd bought all of the testers (buy once, cry once). In a post-EMP world, for example, the Fisch would be worth a lot.
BTW, the technology of using slots and balances for testing metal coins has been around for a couple hundred years, at least.