What you actually need is

1. Certificate of Non Availibility (this states that no such records exist, it is issued by your wada karyala)

2. Birth Certificate (this states your date of birth with your parents name and that it is being issued because there is no such records and has been verified with your other essential documents like passport, school certificate or nagarikta; this is also issued by the same wada karyala)

3. Finally you need an Affidavit of Birth Date (this is done in plane paper where your parents state your actual date of birth and that you are their son and all other essential details, along with your parents affidavit also have one made by your uncle and auntie. have these documents notorized. Then you are good.

Finally such samples are available on immigration voice  particularly trackitt.com.

Good Luck.