VS550 is enough since GTX 760 didn't use much power, although I'm a little bit skeptical of its build quality ( take my words as a grain of salt ).

The PSU..get Antec VP-550P 80+ Bronze RM199 instead..better. Or the 650W version. *don't know the price,can't load the price list..*

The VS650 is actually a pretty good PSU, though it does come with lower tier capacitors (from the review of the 450W model), however the product is well warranted so I do not think it is much of an issue anyway. As for single or multiple rail, there has not been conclusive evidence that one is better than the other, so any would do. I am not sure what series is the Antec model you've mentioned, but the EarthWatts Platinum model is quite ok too. Alternatively, do also consider the FSP Raider which is around the same price range.