Can I get the service book of a government employee by filing RTI

Sir, 1. My father was employed in a Inter college as a Senior Clerk in Aligarh(U.P.). After retirement, he submitted his claim for increased payment to DIOS (District Inspector of schools) Aligarh,office with xerox of service book. 2. After submitting the claim, my father left this world and we got a letter from DIOS office that his Service Book's photocopy is to be attached again with the claim. 3. Problem is that we are not having Original Service Book and due to that the claim is pending since last one year. 4. Sir, how to get the service book by filing RTI to which PIO . Thank You.