Hi Pappy, I will bite, since i am working on some Bundesmarine projects:
This site was pretty conclusive in determining color for modern German navy:
http://www.schnellboot.net/de/bundesmarine-deutsche-marine/diverses/farbcodes-marine/index.phpModern Klasse 143A colors are painted in the darker (dunkel) scheme.
So, for modern day colors:
Hull and Superstructure: RAL 7000 (available as Testors Dunkelgrau 51 in enamel, though there may be some acrylic bottles remaining available)
Deck: RAL 7012 (this was a bit harder to find, but I identified it as Lifecolor UA 108)
Waterline: RAL 9005 (a generic black or very dark grey)