I guess u should be able to cover any of these forest within your budget.
• Jim Corbett National Park , Uttarakhand
• Namdapha National Park , Arunachal Pradesh
Both of these forest are must visit places for people who love wildlife
Depending up on what you want to see. the nearest one would be MP where u can go to Bhandavghard pench and in north hen it would be Jim Crobett. Mp is cheaper compare to jim corbett.
Sundarbans, West Bengal.
Gir forest, Gujarat.
Khasi hills, Meghalaya.
Namdapha National Park, Arunachal Pradesh.
Jim Corbett National Park, Uttarakhand.
Bandipur National Park, Karnataka.
Nilgiri Biosphere reserve, Tamil Nadu.
Keibul Lamjao National Park, Manipur