Is Indemnity Bond required from the Seller?

Hi, I recently got a Housing loan from a bank based on the documents submitted to them. The seller and I completed the Agreement of Sale registration process with the registrar. However, I am bit unsatisfied with the documents provided to me by the seller. The property was built in 1982 and has a pre-sale document from the first builder with 5 rupees stamp (this however does not have any date on it, although the signed date is there). The property was not registered and no stamp duty was paid at that time. The building also has an OC and the flat share certificate is also given by the society with 5 shares of 50 rupees each. Based on these the bank has thankfully given me the loan after having rejected from an major Public sector bank. The society has not done Conveyance ever. For the future, should I get an Indemnity bond from the seller that explains the chain of ownership as well as to mention that any stamp duty that will be required to pay in future will be beared by him? If y