Last year I went shopping for the same thing for an old Univega. I ended up just buying a new quill stem with a 26mm clamp and was able to get the bars that I needed without trouble. One thing to keep in mind though, many compact bars of current design have really tight curves that can be VERY difficult to get through a traditional quill stem. if you don't mind the look, consider finding a quill stem with a removable face-plate.

-Jeremy