Recovering 1963 Property Deed

Is there any way to recover an old deed. I am an OBC. Only the 1963 property deed which is lost, has mention of our caste. My relatives don't have OBC certificate. They married upper caste men and women and refuse to accept that we are OBCs. The property was divided in 2003. In that partition deed, the 1963 deed's number is mentioned. I don't know how to get OBC certificate, as I need it, while my affluent relatives don't want. I know I can't get the original, but even the copy will be helpful. None of my blood relatives has caste certificates, and even my father lied about his caste while getting a government job.