You won't need anything more than 400W, I expect you'll only use about 100W of that generally, just make sure you go for a good brand like Seasonic or Corsair.
Either of these would do nicely. http://www.flipkart.com/psus/compare...UDG347MVWGGKDS
i5 750@3800 - MSI P55 GD65 - Asus GTX780 DirectCU II OC 3GB @1215 & 7000 - 8GB Gskill RipjawsX DDR3 @1800 8-9-8 - Be Quiet! Straight Power E9 500W - Nanoxia Deep Silence One - X-FI Xtreme Gamer - Samsung 830 128GB - Spinpoint F3 1TB - WD RE4 2TB - WD Caviar Blue 640 - Dell U2913WM - Corsair M65 - Thermaltake Contac 29 with Noctua NF-F12 PWM.