Sona case in SS exists for certain watches (Kiran for one IIRC).Agree, even I was little surprised seeing sona case in silver.
However, as far as the above 'Karan' is concerned, the INDIA at the 6'O Clock in large letters is one 'tell'. The indices definitely are glued on - the original has a more 3D effect to it (from the Sona) - another tell; the Kiran, has simple stick indices, not the shaped indices and no double at 12'O Clock. "PARA SHOCK" is usually another tell - the space between Para and Shock is more pronounced. The HMT Logo is usually more raised, rather than look like a flat stick-on. The workmanship of the dial overall is rough - the original typically has finer lettering. The Karan, as far as I know, does not come in this case.