I have the 3D videos. I grabbed them from NUS before Nintendo stubbed them. I have them in .cia format, but the caveat is that because they are system titles, you cannot install your same region's file. So you can install Europe and Japan on US and US and Europe on Japan but not the same one.
And all three regions have a different video. In the US we had OK Go - White Knuckles (and yes, it's in 3D for whoever asked) and the others were something else that I cannot recall at the moment.
I had hoped somebody could convert them to .3ds format so you could just load them with a Gateway or similar, but apparently because they are "firmware files" and not actual games, it's impossible. (boo hiss)
On the other hand, 3D Visual Experience (the one that comes with N3DS that somebody else in this thread asked about) has been dumped as a .3ds, because that's technically a download (also a "legit cia") rather than part of the firmware.
So tl;dr there's no need to get hardmodded just to grab those videos.