I found this on Excelsports, not sure if you have seen it yet. Looks pretty light and adjustable.

"Angle adjustability without sacrificing performance. Contains all the proven quality and features of Ritchey's popular, proven Pro stem with angle adjustability. Precision 3-D Net shaped forged shaft interconnects with a precision broached clamp to create the strongest, lightest, most secure adjustable stem available.

225 grams

8, 10 or 12cm

Fits standard 25.8mm-26.0mm handlebars

Over 45 degrees of adjustment in either direction

4, 5, and 6mm allen wrench required for installation "