Yes, you may go for Maruti Ertiga CNG VXI. With the CNG, its 1.5 liter engine delivers 91.19bhp/122Nm@4400rpm. It delivers a claimed mileage of 26.08 km/kg. As per your requirements, Ertiga seemingly does it all. It won't be a fun to drive car and you might feel it underpowered on open highways. But if you like cal driving or often drive in the city only, it would be a great pick. Maruti Ertiga CNG VXI is priced at Rs. 8.95 Lakh(Ex-Showroom, Delhi). You may check out its on-road price.Do take a drive ride in order to get better clarity. Check out authorised dealership details.
Mahindra TUV 300 is available foe sale and for the availability, we would suggest you walk into the nearest dealership as they will be the better people to assist you because it depends on their stock book. You can click on the following link to see the details of the nearest dealership and selecting your city accordingly - Car Showrooms.