Hi - random question: does anyone know the exact specs (the thread size, bolt length, head size, etc) for the steerer tube pinch bolts on a Cinelli Mash stem?

I broke one today, and have a halfassed replacement in, but it's not perfect. I can't get detailed specs from Cinelli, the importer, Mash, or a shop....bummer.

I can go to a hardware store and compare, obviously. I can also order a ****load of bolts until I find the right one. But hoping someone here just knows...

Thanks!