The Sport Trac is essentially a Ford Ranger chassis, is it not?
If a Ford Ranger with the "big" V6 can't safely and comfortably tow 3000lbs without spending more than $300-$400 on a receiver and transmission cooler, nothing can. You aren't going to find much of a "TRUCK" for $300-$400.
A weight-distributing hitch is ALMOST always a good idea. HOWEVER, some small popups and travel trailers are not designed for the forces of a weight-distributing hitch. You need to refer to the owner's manual for this travel trailer to see if this is the case.
Sway control is definitely a good idea regardless. Better to have it and not need it than need it and not have it. Keep in mind, sway control is not a solution for "known" sway. If you have a sway problem, fix it first, then add the sway control for UNknown sway, such as crosswinds, uneven road surfaces, etc.
