Can Approved Unused H1B Petition used for cap exemption

[sandeepm]

Hi, I had my H1B petition approved in year 2000 but I never got a visa stamped and never entered USA. I have the case number but do not have the approval notice (I797). I moved to UK some time later and acquired British citizenship.

Now I am interested to move to USA and have an employer interested in me. My questions are:

1. Can they utilise my old H1B cap to apply for a new Cap exempt petition?

2. If yes, will they need the old I797?

3. Is it possible to obtain a duplicate copy of the old I797 from USCIS?

Look forward to receive some valuable advice from the wise folks on this forum.