Dear Ajay,
You have discuss with the dealers of Mahindra, Jeep, TATA Motors, Ashok Leyland etc. who would supply suitable vehicles as per your specifications and size. Also you can browse the net. Also you can select new chassis of suitable size, buy from these makers and get the body built as per your requirement from local body builders. You'll have more info in this link -
https://www.google.com/search?client...iz.W2eaZQw6yyI