Bean Blossom is a good line of Chinese banjos in the $300.00 range. Rover banjo line are well made and affordable as well, with comparable prices. I own and love a Deering Golden Era, and their banjos start at about the same as the Chinese models. Check Folk of the Woods website for more details.
As for sitars, here in Toronto we have a large Indian/Pakistani community. These folks have music stores that cater to their communities and sitars, tablas etc are easily available there.