Within your budget, retro-styled bikes you should be looking at are the Royal Enfield Hunter / Classic / Bullet 350, TVS Ronin, Triumph Speed T4, and Honda CB350 trio. All options have comfortable suspension, upright and neutral ergonomics and will be good in terms of fuel economy too.
Of these options, the Triumph bike will provide the most performance and have the best handling. A test ride of all those on your shortlist will be helpful in deciding which is the correct fit for you.