Royal Enfield ad from 50 years ago. The Sherpa was renamed and restyled as Crusader in 1970.

Royal Enfield Sherpa - 1965
Remarkable with the Villiers Engine, the finest 173 cc from Royal Enfield. Reliable, rugged, responsive and elegant – a new expression of riding comfort and superb performance. A machine designed for economy and safety with features drawn from years of past experience. Fitted with the internationally famous Villiers two-stroke engine incorporating a multi-plate clutch, four speed gear box; a robust and maintenance free chainstay – the Sherpa – destined to take its rightful place in the motor-cycle world with a zestful top speed of 90-95 km/hour.
Manufactured by: The Enfield India Ltd, Madras 19
Sole selling agents: The Madras Motors Private Ltd., Madras, Bangalore, Delhi