Hey Tarun,
Firstly welcome to the forum.
For a used 1.3 carb engine, check out chor bazaar. You are sure to find a few of them around at any given time. A Baleno engine would be a tough find though.
I suggest getting a used MPFI though. The cost of the conversion should be around Rs.25,000 - 30,000 including the engine, ECU and wiring harness.
Rt
p.s i don't seem to recollect your car. Maybe you could post a few pics of it
here