Our son who is a US citizen is applying I-130. Once approved we will go for Counsellor Processing in India. We were married 53 years back. The Registration was not compulsory then. There were no offices nearby to our place of marriage then. It was not taken seriously. In spite of best efforts we are not able to get even "Non-availabilty certificate for non-registration of marriage". Will US authorities accept TWO affidavits signed by those who had witnessed the marriage then & not insist on Non-availability? Kindly inform.