I know I'm new here and not really sure on the rules of bumping MEGA old threads like this, but I've just been playing a VERY old game in my web browser (really should be working but ya' know), and I thought to myself
"I wonder if there's any archived Final Fantasy stuff laying around here?"
Anywho, I came across this:
https://archive.org/details/square-enix-commercial-pack
It's a huge collection of old commercials (adverts to me and my UK brethren) for loads of Square titles!
This website has an absolute plethora of content on it which aims to preserve all different forms of media and keep them in one place. Just type in 'Final Fantasy' and see what I mean. I've not gone through it with a fine toothcomb, but hopefully there might be something there that'll pique individual interests