For the availability of spare parts, we would suggest you walk into the nearest service centres. You can click on the following link to see the details of the nearest service centres and selecting your city accordingly - Service centre. Moreover, for an idea of the prices of the spare parts, you may follow the below link - Spare Parts.
As India is all set to shift emission norms to the BS6, so the carmakers and authorized dealers are trying their best to clear the BS4 stock ahead of the deadline. If you specifically want a Honda BRV car then we would suggest you to have a word with the brand as they will be the better people to assist you with the availability of the car in a particular city.