Hi aspirant.

Well ,500 is quite a good score. The 10% reservation for economically weaker sections (EWS) will be implemented from this academic year.The National Testing Agency (NTA) has re-opened the NEET 2019 application correction window inviting the candidates to apply for Economically Weaker Section (EWS) reservation. By applying under EWS quota, candidates will be able to avail the benefits in the admission process as the medical colleges or institutions with EWS seats will conduct a separate counselling round for all such candidates.

Since this category has been added only this year we cannot accurately say the cutoff for this Category. 

Also you can predict your college using;

https://medicine.careers360.com/neet-college-predictor?icn=NEET_clgpd&ici=NEET_text-mapping

Good luck!!