The Strom Motors R3 intially will be available in Delhi-NCR and Mumbai followed by Bengaluru and Pune in the second phase. For more details, you may visit the official website of Storm Motors.
It would be unfair to give a verdict here as the battery life would depend on certain factors such as driving conditions, charging cycle, timely maintenance, etc. Moreover, we would suggest you to get in touch with the nearest authorized dealer as they would be able to assist you better with the exact price of the battery.