Hi
Taking last year least marks into account I can say that from OM category least marks to secure a seat was 440 in sher e Kashmir institute of medical sciences,soura, Srinagar ,from SC it was 361marks in same college and from ST it was 266 marks in government medical Remember that Cutoff varies every year based on number of students appearing in the exam, difficulty level of the exam, students scoring more marks than you and category to which you belong.
You can look for cutff of various colleges in Jammu and Kashmir from Link given below
https://www.google.com/amp/s/medicine.careers360.com/articles/neet-cutoff-j-k/amp
Hope this helps