Just some REALLY tough polished-semi, or straight-up gloss black paint was used on the originals, from what I can tell, with the three I've had.
A couple good ways of getting a close match:
-Paint with Alclad's Gloss Black Base, let cure 24hrs or so, then burnish w/paper towel
-Paint with Krylon or Rust-O-Leum Professional Semi-Gloss Black, let cure at least overnight and again, rub that sucker down with a paper towel
The trick, for me, seems to be in the final polish/finishing of the paint. Lemme see if I can find some pics....