@yawar538 @imranuh @huzaifa_khalid
Finally after almost a week, I finally got managed to mount the Nexus 7 2013 in my Santro. I visited Hall road, Montogomery road, Hafeez Centre but couldn't find any Tab holder or stand.
So I decided to mount the Tab in a new way.
I visited a nearby Photo Frame maker and showed him my Tab and asked him to make a frame for my car. He saw the place of mounting in the car and measured the dimensions of the tab and made a frame for it. The material he used was a mixture of wood,rubber and plastic and material was such that it wouldn't damage or put scratches on the corners/edges of the tab or it's body.
So here's the frame that was made by him, it cost me Rs. 300.
I asked him to cut the frame in such a manner from the sides so that I can plug in the aux in the 3.5mm jack and also so that the power button and volume rocker be accessed easily
He attached a hook on the frame so that the hook can hold the Tab from the bottom. and by displacing the hook, the tab can easily be removed from the frame so that you dont have to leave the Tab in ur car when u r not inside it.
I used industrial strength double tape to paste the from on the dashboard's wall.
The tab was placed inside the frame, the hook was placed in the closing position and we are done.
Now I can play videos, use Sygic for Navigation(awesome) and take my Tab home whenever I leave the car 
