I'm referring to the bolts that hold the faceplate onto the stem, rather than the one that holds the wedge on a quill stem.

I've got several different bikes, and one thing they have in common is that the cheap factory bolts that come with the stems rust within a couple of months. I'd like to replace them with stainless bolts. Is there a standard size for these, and if so, what is it? If not, I've got four Deda stems and one Specialized.

Thanks!