Actually I'm specific about those two cards because of this previous thread of mine. That user told that these cards are the only cards which are under $150 and can provide 400+KH/s. Obviously I can get only used cards under my budget. That's why I'm specific about it.
You asked in the international forum, do you expect to just apply the conversion rate of $/Rs and get it at that price? 7950's are available on amazon for 300~350$. Same stuff is 23K in India. 6950/70 is a pretty old model that's why you could get it under 10K, they'll be mostly out of warranty: a bill is a passe. Just because you got a reply over there to buy a 6970 doesn't mean you shouldn't do your research, look here https://litecoin.info/Mining_hardware_comparison
A 6950 isn't much behind from 6970, but if you can get a 6970 for almost same price that's a better deal obviously.
R9 270x are pretty new, you won't find used ones. 7870...maybe, but that's a far better deal.
A new card will consume less electricity (unless you have free electricity) and have better resell value. 2 years down the lane if you wanna sell your gear you might not even find someone willing to buy a 6970.