Aftermarket market definitely. Early RRs had the wing mount stick, my 1987 model the aerial was part of the heated rear screen element.
Understood to have been fitted from new, I have owned it since 1991 and previous to that it was registered to Land Rover.
it has a VIN starting with DA like mine maybe, which was when the aerial was incorporated into the rear screen alongside the heating element. Item 3 on my parts book page.+ one, mine is an '87 as well. Aerial incorporated into rear screen heating element in Nov. '86.
Thanks for the responses and information. I saw from the Parts Catalogue that the only aerial options were a post or through the rear screen element but I find it hard to believe that, if there had been a problem with the screen element aerial, LR would have gone to the trouble of installing a roof aerial which would necessitate moving the headlining rather than just replace the upper tailgate.
Out of interest, how does the aerial lead attach to the heated screen element?