As your score is little less than the marks that the Top IITs seek for admission in M.tech so your chances of getting call and taking admission in top IITs is less. But you may apply for some, like

1. IIT Dhanbad

2. IIT Mandi

3. IIT Indore

4. NIT Sikkim

5. NIT Manipur

6. NIT Meghalaya

7. NIT Nagaland

8. NIT Puducherry

9. NIT Goa

10. NIT Arunachal Pradesh.

You will definitely get chance in any of these colleges in Mechanical Engineering brand in M.Tech. Good Luck !