That'll be the Cinelli 1A then
I'm not sure about prices rising, they're not rare, I reckon it was the most common stem at the time.
My favourites are the 3ttt 78 and 3ttt Record. The 3ttt pro chrome was welded steel with a strange dull finish.
If you want a welded steel stem, the plated & polished version of the ITM Eclypse was a class act. Appeared on a lot of early '90s pro bikes in preference to the similar-looking lighter (but presumably whippier) Krystal titanium stem from the same maker. Currently riding them in quill and Ahead formats and no grumbles about either.