It was created for the video by the animator.
Two other music videos are also featured within "Money for Nothing". A Hungarian pop band Első Emelet and their video "Állj Vagy Lövök" is displaying as "Baby, Baby" by "First Floor". (The name "első emelet" translates to "first floor".) Első Emelet was extremely popular at the time in Hungary, although their videos might not have appeared on Music Television.
The other is a fictional, supposed MTV video "Sally" by the Ian Pearson Band (Pearson was one of the animators of the video).
"Ian Pearson and Gavin Blair created the animation, using a Bosch FGS-4000 CGI system. The animators went on to found computer animation studio Mainframe Entertainment (today Rainmaker Animation), and referenced the "Money for Nothing" video in an episode of their ReBoot series. "
and from WFMU's site:
" Another minute thirteen seconds later there's a black and white video of a woman in her late twenties, early thirties in alluring black lace stockings and white panties (that more or less double as toilet paper) glaring seductively and taking her frustration out on a kiosk. This band, its song and accompanying clip--The Ian Pearson Band's "Sally"--are completely fake. Ian Pearson isn't even a musician; he's the animator of "Money for Nothing" and close friend of the Knopflers."