He should have told you it was the Mach 460. Thats the upgraded stereo in the ford line. There was a MACH 1 package out but I think that was in later years. It came with a shaker hood w/ functional scoop & a MACH 1 paint scheme.
The miles are on the high end so it really depends if the car was taken care of or not. Just keep in mind that you will be making payments on a car that will also need repairs now and then to keep it in good shape.
If it's in good shape inside & out, go for it.