Any quality 500+ watt power supply should handle the system without issues.
You have a 125 watt cpu. Lets add 150 for good measure.
GTX 760 @ 170 watts. Lets add 200 for good measure.
Motherboard and memory, lets go 75 watts.(should not take much power to be honest)
Hard drives average about 10 watts. lets ad 15.
Giving an overestimate of 440 watts. Truth be told the system will not use this much power, but running a power supply to close to the max is not great anyway.