With a Score of 463/720 being from General Category, your son has negligible chances in securing a seat in Government/State Colleges in Karnataka, even under State Quota. You should rather target State/Private Medical Colleges in Bangalore and rest of Karnataka through COMEDK Medical Counselling or Management Quota. Since youre from Karnataka, incase youre financially strong your son  has excellent chances in securing MBBS at KMC Manipal, perhaps has a very high tuition fee in lieu of excellent Medical Education.

For more information and College Prediction do follow the link below

https://medicine.careers360.com/neet-college-predictor?icn=QnA&ici=qna_answer