My wife loves the old hats, and wished more men would wear them to work like long ago. I would, but I can't find one to match my boxers. Ahhh, the joys of working from home...
My husband started wearing a nice fedora to work, and has gotten a lot of compliments and queries as to where he bought it.
Try a nice Toquila straw Panama hat. The nice off-white color should go with everything.