Welcome aboard Poccur, hope you enjoy your stay here!
About the IOF made SLR, you'd be hard pressed to find an Indian citizen who owns one, as:-
1) Licensing for semi-auto long guns is VERY restrictive.
2) Ditto for rifles chambered for 7.62x51 which is on the list of restricted calibres here.
and the clincher....
3) They were never sold to civilians, just military/ para-military/ police forces.
Do post photos of your build, it should be interesting to see it take shape and also to know which 'standard' parts fit and which don't!
Cheers!
Abhijeet