MAT

MIT is far better than that of Indra. So, opt for MIT instead of Indra.

You are easily getting Sinhgad-Pune and Indira. Also Try for MIT Pune.

MAT exam is held approximately four times in a year. So that, if anyone want to give MAT he/she can easily choose his best time to go for this exam. If you are searching for Top B Schools than this should not be a choice. If you give CAT and CMAT exams and after this you couldn't get good marks in it than you can definitely go for it. This exam will give you a decent college and the main benefit of giving MAT is that you would know about the exam strategy and can conclude your ability. MAT college are affiliated by AICTE and some of are good college that you can apply for.

You can apply to colleges which accept MAT scores. If you score well, you will definitely get a seat in a good college. Please refer to the link provided below for a list of top B-schools which accept MAT scores. This ranking is based on rankings published by The Week, Business Today and National Institutional Ranking Framework (MHRD).
https://www.shiksha.com/mba/ranking/top-mba-colleges-in-india-accepting-mat/2-2-0-0-306

It is one of the best books for MAT. I also mentioned few books which you can also refer to while preparing:
1. Mission MBA MAT Guide by B S Sijwali and Tarun Goal (Arihant Books)
2. MAT (Management Aptitude Test) Entrance Exams with Practice CDby GKP (G K Publications Pvt. Ltd. ) covers,
3. The Pearson MAT Super Course with CD (Pearson)
4. Study Package For Management Aptitude Test by Arun Sharma (Tata McGraw-Hill)
5.10 Challengers MAT 10 Mock Tests for Management Aptitude Test by Dharmendra Mittal (Arihant Publications)
6. MAT Score Accelerator (Odisha Publication). .

Yes, you are eligible for Amity with that score.

MAT and CMAT consists of basic quantitative aptitute part,english and logical reasoning question.For detailed syllabus go to official website of AIMA.