It's A3 size glossy paper gsm 250, pics(hd) were downloaded from internet only.
You need to find a printing shop that print's digital images. If you can download hd image's then maybe A2 size sheet's can be a good option too .
But ask printing shop owner , that image that you downloaded is fit for A2 size or A3 size before printing.
For the prints : Just roam around your local market and see the BIG yellow sign of XEROX COLOUR PRINT n all. . just walk upto him and do your thang. Unless Mumbai doesnt have printing shops :s, then you can maybe take up the issue with Shiv Sena.