There's simply to many variables without being able to see it. If you could throw up a couple of pictures there's a chance of getting close to the decade it was made. I have a Hemen from what I believe is the late fifties, early sixties which doesn't have India written on the tag. I understand that was something that came later,although not exactly sure when,late sixties maybe. I also had a Sarod that had "made for the Ali Akbar College" written on tag. I understand this was something that was done in the seventies, and on his style of Sarod.
As far as the finish, tun wood,(red ceder) Sarod's tend to get a dye or color put in the finish as there grain is not as nice as teak, and you can hide a multitude of sins!.That might explain the finish, although tun Sarod's can look very nice in there own right.
The head stocks on two piece Sarod's are attached just above where the fingerboard ends. You should be able to see a hairline cut on the underside where the two pieces are attached. Hope this helps.