As an Assamese resident, can I get affidavits (declaring income, family members, and address) stamped by the Home Department in Delhi for apostille processing by the Ministry of External Affairs?

No, affidavits for apostille processing are not stamped by the Home Department in Delhi. They are typically attested by a notary public or a designated authority in your state of residence, Assam. Once attested, you can then get them apostilled by the Ministry of External Affairs.