Gopal,
Your consultant's advise is suprisingly accurate. You would have to provide an university attested transcripts in a sealed envelope.
If you are out of India, try and ask your relatives/friends to get it done for you.
I had finished my degree in the 90's too, and had got my transcripts from my extremely beaurocratic university recently.
Sure it's a challenge for you, but it boils down to how keen you are to migrate and how much efforts you would put for it. Why provide them with a chance to reject your application.
In case you decide not to pursue the above, at least provide a notorized photocopy along with a cover letter explaining why despite all your effort, you can't provide sealed transcripts from the university.
Also, this is a sub-forum for IELTS, not too many members visit this section. Post any queries in the main section (skilled workers) and you would be sure to get more replies.
All the best to you.