With the 5.0L Mustangs, Maximum Motorsports is a very popular choice with our customers. MM really specializes with those years.
MM has a nice suspension package line-up. Check out this link
http://www.stangsuspension.com/store...?idCategory=61
More specifically, you may want to start with the MM Road & Track Box. It is a pretty "sporty" suspension kit as you requested, and really includes everything you need to get started.
Here is a link to the exact Road & Track box for your car...
http://www.stangsuspension.com/store...?idproduct=191
NOTE - You will need to upgrade your spindles to 87+ Mustang spindles. None of the 87+ struts will fit on your 87 without doing this.
Sincerely,