Just wondering if anyone can ID this stem. I need to know what shim to look for. As you can see the screw and clamp are missing.

yes, thats a 1/R

It's not really a shim that this needs, it's a screw and a specific wedge that presses against an opposing wedge-piece with a half-tubular clamping bit with ridges. A picture would help, but I don't have one
You also might need the plastic clip-in plug for the front that has the "C" winged Cinelli logo...or not, many folks discarded them.
I'd say offer to trade it to a Pinarello owner for a blank un-panto'ed one, that should get a bite.

Thanks,,it is actually going on this bike:


I thought it was the same as the 1r stem on there now. .and it is..so I should be able to take the parts I need from the current stem.



Still looking for the right 26.4 Cinelli bars to replace the Nittos.

panto is way cooler than not on that bike. That looks like an original stem, too, and not a reproduction.

Do change the bar out, as the current combination is a little dangerous...you can't ever get the 26.0 bar completely tight. Hit a big bump and your brakes are pointing at the dirt, and, well, you can imagine...

Yeah.. i rode it once as is.. might take it out for a short spin again..but riding the Calfee until I can get the right bars.

OBTW the leather on that Regal seems paper thin..already have a small cut on the tail edge. bummer