Sorry to disappoint you but even with state quota you wouldn't be able to get admission in a government medical college in Kerala as for that you need to have a score above 550 and under all india quota you need to have a score above 600 to get a seat in government college in any state. But you may get a seat in low private medical colleges with this rank. 

To predict those colleges please go through the below given link of neet College predictor.

Https://medicine.careers360.com/neet-college-predictor

Thank you.