This may be TMI about my dressing habits, but if they're all black... they match in my eyes.
Seriously, my DH and I have a ton of white tubesock-type socks, and they all seem from slightly different types; some have a grey toe, some a darker grey toe, some are grey all across the bottom, etc. I just pair up any that are left after matching on the grounds that the only visible part is the ankle bit. The matchy-matchy socks go in the top drawer and the almost-matchy pairs go in the bottom, so that at least we know whether we're heading out into the world in slightly mismatched socks.
Unless your husband is in the habit of taking his shoes off in public, can't you just pair them up as closely as possible? Or am I just that much slobbier than the general population?
(Seriously, it was my DH that first instilled in me the idea that socks should match at all.)