Oh yeah, Gogo was fuckin' crazy.
Her weapon's a meteor hammer, which is actually Chinese. She uses a single-hammer version as opposed to the more common two-hammer.
As for feasibility of the actual Vampire Killer, there was also a literal chain whip in Chinese weaponry in centuries past. Rather than be a series of links, it used long metal rods (not really rods, but I can't think of a better word), the most famous being the nine-link. They typically had a sharp dart or hook of some nature on the end, rather than a mace ball as the VK does. Due to how they were constructed, they could and can be used more like a regular hide whip. The longer links could wrap around targets better than smaller O-links, and allowed for better control over the length of the weapon. The weightier construction also meant that force carried through the whole thing better, which when coupled with proper speed makes it pretty effective.
Obviously we know the VK isn't one of these, but it is interesting to note that a practically-usable chain whip does exist.