Hey

You can attest your documents from gazetted officer nearby of your locality ,so there is no need of sign from principal.
Some gazetted officer are :-
IAS,IES,IFS,SDPO,DIB,CP,DGP,JCP,IGP,ADLCP,DIG,DCP,SSP,DCP,SP,ASP,ACP,DSP,COLONEL etc are all class A gazetted officers. Attestation of copies of original documents for academic or immigration can be done by Only Class I and II officers mentioned above and bank managers of Nationalised banks.

Thanks !