Carol is referring to the General Register Office [England and Wales] which houses Civil Registration - the central repository for copies of births, deaths, and marriages.
In the Isle of Man the General Registry issues copies of births and deaths from 1878, marriages from 1884, and adoptions from 1928. Carol, if you write to the Chief Registrar, General Registry, Finch Road, Douglas, Isle of Man, British Isles, giving your names and 1878 onwards birth dates, they will issue the certificates - you don't need the index refs, but you will need sterling to pay the costs of the certs.
Sue