Redline and weber carbs direct sell the real webers currently (may be others, but I don't know of any)
Weber carbs direct is cheaper, but they don't pre-jet even for specific kits, so you have to rejet and pay for tuning (found this out the hard way)
Redline is pretty good with their jetting so long as you buy the kit for your vehicle. If you buy a weber and an adapter seperate, you get the generic jets so you have to pay for rejetting and tuning.
My opinion, buy from redline at their website, not ebay. This way you know you are dealing with the company and not someone selling ripe offs.