I found a PP Super I like but its chambered in 9X18.  I was wondering if anyone makes a 380 barrel for this model.  There were some imported in 380 put they tend to be very expensive.

At a minumium, you'd have to replace the barrel and recoil spring.

I simply don't know if that's all that would be required.  I'd hunt up the Walther forum and ask the experts.
waltherforum.com/

Gun Parts does sell several Walther PP .380 barrels, including an extended version.

www.e-gunparts.com/productschem.asp?chrMasterModel=2100zPP

No that gun is chamberd for 9x18 ultra not 9x18 makorov

A walther pp barrel will not work the following is a reply from a thread on 9x18 ultra

Fionchi (sp?) sold some a while back. I'm sure you'd have to go with a Euro manufacture. Since you know the difference between 9mm Mak and 9mm Ultra, I won't bother with the usual warning.

Some Sig P230s in UK service were chambered in 9mm Ultra as well. I had a Walther PP in 9mmU for a short time, but never shot it because I never ran across any ammo. It was pretty big for a PP, especially the grips. Nice workmanship on the gun though.

Odd-ball gun and ammo, but it would be interesting. Good Luck finding it.

Ross