If you are looking to overclock then you may want a 550w but it will cost you more
There is also the Corsair VS 550w for 3250 INR but VS series is not as good quality as the antec.http://www.flipkart.com/corsair-vs550-550-watt-psu/p/itmdg36xx8yzgjrs?pid=PSUDG34775NHYDHK&otracker=from-search&srno=t_1&query=corsair&ref=cb364a2e-e63f-457b-bd3d-2cc046cb0806
Personally my recommendation is to save up a bit extra for the antec 550w or go for the 450w that jonoj96 posted. The 550w would just give more room for future upgrades and overclocking but the 450w would work.
I believe the corsair VS has some cheaper components so it may not be ideal for overclocking but they seem to be quite popular for the price and are definitely better than some of the really bad PSUs