If you donot have a space constraint , suggest you look for a dedicated HT setup with alAV Reciever and bookshelf speaker. In your budget you would have to look for used ones.
However if you just want a louder and a larger soundstage than your TV , soundbar is just fine specially within your budget. Please be advised that you won't be getting that cinematic and experience of a dedicated HT (which also depends on the room size , acoustics and many other factors)
For soundbar , I can only recommend what I have experienced personally. I came across a Polk Magnifi mini soundbar recently and found it to be really good for its size. Decent soundstage , loud , dialogues are clear and base is adequate for a small to medium room. Slightly above your budget but you might want to check. If you prefer bass , boat or zebronics are for you which are designed keeping Indian bass lovers in mind. For a more natural sound , check if LG / Yamaha / Polk works for you.