What would be cool is if it was all set in India. So, we see the modern India and then they go back in time to 1950's India. If they do that it could be fun.
1970s now, not 1950s. The relative size of the time jump is critical to the plot.
I'm not going to claim to be very knowledgable on international history or anything, but I would easily believe the the differences between 1970s India and current day India are a bit more extreme than the differences between 1950s America and 1980s America. This could be an interesting movie to see.