Not sure about where Vortex's are made but I can speak to the quality of them as I am sure you have seen with your current pair. My dad has used Leupold all of his life and swears by them, even has me hooked on them. He is really rough on his binos and wanted some for work and throwing in the truck. I told him to get the Diamondbacks just simply for the life time guarantee and he is now a Vortex fan. He went out and bought a Razor for hunting and says it is the best pair of binos he has ever owned. We even did a stare and compare to our $250 Leupold's and prefer the site quality on the Vortex. I have not looked at the Vipers but the Razor is exceptional.
As far as vendor I think you have the best idea of checking out sales in the coming weeks. The last few binos I have bought I actually found a lot cheaper on Optics Planet.