1.
www.fordpartsonline.com shows front pipe (which I assume contains cat, due to it's price) as being $606 (list $757).
2. Try a wrecker.
3. Modify (i.e. gut existing cat) and get MIL eliminators (MIL = Malfunction Indicator Light = CEL).
Lot's of plugged or gutted cats on the v6 engine equipped cars, don't recall a Zetec with the problem.