so finally, the PC was bought 2 weeks back. here's the break-up:
1. Motherboard + CPU --> Asus M5A97 LE R2.0 + AMD FX6300 --> 12,200/- (prices for most of the things have gone up. hence, LE R2.0 was bought, instead of just R2.0).
2. GPU --> Sapphire HD7870 2GB --> ~15k-16k. don't remember the exact amount (here too, the seller confused my friend between XFX and Sapphire. XFX was a little cheaper. however, i kept on insisting him to buy Sapphire only. the seller admitted that he doesn't have much idea about differences between both the brands and is just suggesting XFX as you guys have a limited budget and XFX is cheaper. i somehow convinced my friend after showing him some google-searches on the shopkeeper's computer and after asking an online friend of mine, after which this hurdle was also successfully cleared!).
3. RAM --> Kingston HyperX 4GB X 2 1600MHz --> ~2300/- for each module.
4. PSU --> Seasonic S12II - 520W --> 4100/- (the seller had kept on harping to buy VIP, CM, Antec PSU, and friend seemed to buy this; and seasonic also wasn't there in stock, and Tirupati's godown was closed and was to remain so till 3-4 days ahead. but i remained adamant and kept my friend on hold from buying one of those PSUs. ultimately, after a google-search on the computer available in the retailer's shop, i was able to convince both, my friend, and the seller, to go for seasonic. he then agreed to send the seasonic PSU to my friend's home when Tirupati's godown opened up).
5. Cabinet --> NZXT Gamma --> ~1950/-.
the purchase was made at R.K. Infosys (Lamington road). enquires were made at McCann Infosys (Bharat bhai) and primeabgb (quite expensive) as well. it was a close call between R.K. and McCann, but after much ado, we finally decided upon R.K. the seller/proprietor (Rakesh Shah) is a jolly-good and helpful seller. he gave us the best deal of all. assembling was free of cost.