Hi, it was me who posted the footage on my You Tube channel, The Rangers Archives.
As several posters have mentioned, the footage comes from the sponsors who were the only ones to film the match. Archie's commentary was added on when it was shown on Football Focus about a year later which is where my version comes from.
In the months following the match Drybrough screened the footage around the country in clubs etc. I am not aware of any other footage of the match, and have never seen Cooper's goal from the Main Stand camera sadly.
I believe this is the best quality and most complete version of the only footage that remains of the match.