This advice is worth exactly what you paid for it but I would avoid Vector Arms at all costs.
I had to deal with them [while working at Tac Pro Shooting Center] concerning three separate HK-clones that they built that we acquired NIB directly from them and every one had issues ranging from a broken firing pin and defective magazine on an MP-5 pistol to improperly configured [nonfunctional] recoil spring assemblies on an SBR G-3/HK51 pattern.
The company was a pain to deal with. Customer service was a joke.
I would run away from anything made or marketed by Vector.
It was a serious question, mean spirited or not. If I happen to know someone who has what he is looking for, I want to know whether it's worth the trouble to talk to the owner about selling it or if this guy is just trying to lowball.