You are possibly talking about the Fiat G.80 or the more developed G.82. They were jet trainers in the same class of the Fokker S-14 Machtrainer.
Because the U.S.A. dumped T-33's at NATO countries for very low prices the Fiats were never put into production.
However, Italy had more jet trainers. Procaer built the Cobra as a single prototype, which was in the eighties further developed into the Promavia Jet Squalus. Both machines were only built as prototypes!
Another unsuccesfull trainer was the Caproni Trento F.5 light jet trainer.
So, just pick your choice. If you want to see photos on the forum, ley me know since I have them!