It looks like a B series bullet which had the G2 engines imported from the UK and sold in India from the early to mid 1970's. This was a transition period where Enfield India was planning to start manufacturing as much as the components for the bullet in India, which also explains the frame being a bolted type near the gearbox top mounts. Roughly around 1976-1977, the bullet 350 was built with parts made in India. One of the main differences in this engine compared to the G2 bullet engine was the weight of the crankshaft had reduced from 9.5kg on the 350 G2 engine to 9kg on the B series engines. After the B series ended, the crankshaft weight of the Indian 350 bullets reduced to 8kg.
I think someone might have changed the steering top yoke. It's also supposed to have 6v electricals