Why sticking with Intel ? In budget section, AMD is not at all a bad option, have you ever given that thought ??
Just expressing my views though, bellow config
AMD APU A8 3870K @ 3.0 GHz 3.0 GHz / 8 Core / HD 6550D DX11 @ Rs. 6,500
ASUS F1A75-M LE ~ SATA3 / USB3 (Find a lower spec board for money saving) @ Rs. 6,500
Corsair or G.Skill (4x2) 8 GB 1600 MHz @ Rs. 4,000
WD Green 1.0 TB ~ 64MB buffer / SATA3 / 7200RPM @ Rs. 5,000
DVD RW Any @ Rs. 1,000
Antek 450 @ Rs. 1,800
Cooler Master 311 / 310 @ Rs. 2,200
Total 27k
You are from Kolkata, chadni prices are really lower than Web Prices, like WD in web is around 5.2k which in chandi goes at around 4.2k

. Try for a local el cheapo cabi if you want to save some money there

too, 1k i guess can be saved from there too
Also some exp member can give you a lower spec board since this board is having CrossFire, which is no use of your, try from Gigabye, should come in at around 5k, thus getting the system in 24k mark..