Yes, the regular DSSD rep (including BKs) the rehaut is engraved (thicker than the gen I might add) and a simple careful application of black enamel would fix it (unless this is a defective one that has an F instead of E, which I doubt).
As for the 50, I would not touch that. It's barely visible (most people would confuse that with some dirt on the watch) and matching that color with enamel is a little more involved. Doable but requires experience.