Sorry, i've not got much to go off
The music video is filmed on the top of a mountain.
The band/ singers are dressed like hippies with long hair/ beards.
The song is quite old......maybe eighties but I may be way off the mark with that guess.
The song is upbeat and very familiar- maybe used in films.
During the music video, there's a door that appears and opens into thin air on the top of the mountain.
I seem to remember the band or song having the word rust or rusty or rusted in the name but that could be wrong.