I usually avoid funerals but I allowed myself to be persuaded to attend my uncle's funeral last year. None of the women present (including close family members of the deceased) seemed to be dressed specifically for a funeral. They were simply dressed rather formally, with nothing particularly garish.
I think you'll find that 'funeral wear' isn't really worn these days. (I did wear a black tie for my uncle's funeral, which I never bothered to do for my either of my parents' funerals, but I noticed that most of the other men didn't. Very few of the women wore hats and even the vicar was dressed without any great degree of formality).
However, if you're set on a bit of formality, JimF's suggestion of black and white sounds fine to me.