Is this a good price

that is correct. what year are the parts for? i have heard of people using fox trannies in the sn95s but never seen it. i would just get the sn t-5 and use it. then you know for a fact that it works.
 
Watch the bellhousing. The one from the 3.8l will bolt to the block but requires a 164 tooth flywheel. Mustang 5.0's have 157 tooth flywheels. All the other parts will work fine. (You should stick with the SN95 trans/BH, though.)