I can remember only two services that used V23 modems for communications: Minitel, in France, and Videotexto, in Brazil.

So I think that your best chance is to find a US Robotics for the French/European market. I remember that the older Sportster (the 14400 ones) had V23, but I never knew anything about PAVI, maybe it's some user defined register in the USR line... they had a plenty of this...