Hai aspirant! First of all , I appreciate your efforts and hard works . YES.You can get the seat in Stanley college .Just make sure your keep continuing the mock tests and be on safer side sigh extra cut off . 

Well that's a very good score. With continuous practise you will do even better. Getting 300+ in mock tests is a very good sign. For Stanley Medical College, the opening rank for 2017 first round was 729 and closing was 1320 for general, for Scheduled castes it was 10280-16527 and for Scheduled tribes, it was 32939-35473. All the best for NEET.