Josh,
I saw light brown (medium to dark tan? anyway, a whole lot closer to brown than black or white) FJ ComfortSof socks at a course I played yesterday. There were three styles: Roll Tops, Low and Full length. I asked: They don't ship stuff, but said the socks were from previous years and they still had a few left. They suggested you contact local courses in your area that sell FJ and maybe one of them will have some left over as well. Or, you could drive down to Green Harbor (Marshfield) MA.
Good Luck