Definitely not your average home system usage.
I would suggest NOT overclocking at all as I suspect stability is most important.
Though I'm not in India, I am pretty sure Kingston and Corsair are readily available in your region. I could be wrong though.
Kingston - memory finder link
KVR1333D3N7K2/8G - kit of 2x 4GB
KVR1333D3N9K2/8G - kit of 2x 4GB
KVR1333D3N7/4GB - single 4GB module
KVR1333D3N9/4GB - single 4GB module
Corsair - memory finder link
CMX8GX3M2A1333C9 - kit of 2x 4GB
CMX4GX3M1A1333C9 - single stick of 4GB