Hiiii vibhanshu....

Yes, it is a quite good score to be in the merit for private medical colleges.

The NEET cutoff 2019 candidates belonging to UR category have to score a minimum of 134/720 marks for qualification in NEET medical entrance exam. The OBC/SC/ST category candidates need a minimum of 117 marks to qualify NEET 2019 exam. 

Thus getting 500 will land you in a good college. If you can score 500+ then there will be high chances that you can also apply for deemed universities and colleges.

All the best:)