I can't say whether or not that car is a good buy. You usually get what you pay for dude.
The SVT is Special Vehicles Team, they build the Cobra.
Converting to an SVO would also include swapping everything!
The SVO had a completely different internal setup with forged stuff a plenty, they made 200hp or so in 1985-1986 with the intercooled turbo engine.
My personal thought on that Mustang, is since it's a 4spd, it's got the A4LD automatic, which is a pile of **** (I've rebuilt them on more than one occation), all manuals were T-5 5spds. Because of that, I really wouldn't be too anxious to pick it up, unless I was planning to do a bunch of work and swap it over the the 5.0L drivetrain.
Unless you are mechanically inclined, and you have a couple thousand extra sitting around to do a proper 2.3L to 5.0L swap, don't get it. Save that extra two grand, put it together with the 1k this thing is gonna run and buy a real 5.0.