Sorry I'm not too familiar with the vs series as I haven't worked with it much, I imagine they shouldn't be too bad as they're corsairs, and corsair makes quality products you could also take a look at seasonic PSUs as they're great. You could go with the one you initially suggested.
Basically the K denotes an unlocked multiplier on the CPU. The clock speed of the cpu is determined by the bus speed*multiplier. the 3570k uses a 100mhz bus and doesn't like to move much.
so as the 3570k is listed with its 3.4GHZ clock it has a multiplier of 34
100mhz*34=3400mhz
when you overclock it you change that multiplier as it is not locked.
so say we wanted the CPU to run at 4ghz we'd change it to 40.
100mhz*40=4000mhz or 4GHz
if your going to overclock it though you'll want to change the cooler though, this can actually be done even if your not overclocking the cpu as it will keep it cooler and just be less stressful on the cpu in general. You can get some coolers for really cheap though so don't worry, you won't need it if your not going to overclock but they're nice to have.
Heres a very popular cooler that i typically recommend, it appears to be a bit more expensive where you live though but it is still a great buy
Cooler Master Hyper 212 EVO Cooler
http://www.flipkart.com/cooler-master-hyper-212-evo/p/itmd7pfht3crxtnf?pid=COLD7PFHHUXGKHZW&ref=f7e8c6a4-1d3e-47ed-840a-ad8353050042&srno=m_1_1&otracker=from-search&query=coolermaster%20212