The 3rd generation ('97 and later) Escort/Tracer sedans (not sure about the wagons) have a 13 mm rear sway bar. The 2nd gen wagons use a 19 mm sway bar that will bolt up to the 3rd gen if you use the bushings from the second gen.
I have a 91 GT, I am unsure of the original's size was, but it was pretty stout. I have upgraded to a Suspensions Techniques sway bar kit puts an additional 3/4" bar in the front and a 7/8" bar in the rear.
sorry, sold my spare bar to Pextor a few months ago. will have a 2nd gen LX bar available in the near future, but it's not as bit as a GT. It will probably get junked with the rest of the rear subframe