Using a shorter rear shock could be a way of slacking out your frame's head angle (thus raking the fork out) and lowering the bike.
No welding necessary. Alas, I don't know if a shorter rear shock, sprung and damped appropriately, is readily available in India. Royal Enfield Zone in New Delhi may be the place to ask for most of your wishes. Prices are going to be relative to your location...much cheaper than the rest of the world for lots of it, possibly way more expensive for some of it. Not too many on the forum can really give you an answer.
Also, for what it's worth, throwing wide tires on a 350 is a losing deal in terms of performance. Obviously you want the aesthetics; your description of what you want is very Harley-like. A 3.5" tire front and back is probably as wide as necessary and practical, IMHO.