The hat, once so essential - now? I have a Stetson cap, but it's not often seen as I wouldn't want it blown away by a strong wind. We see lots of marvellous images from the Boom Years: my pride and joy is a black and white ad for Stetson - 'Stripes Up the Band': quintessential Ivy guy in hat and exquisite pin collar. But carrying it off now? I'm doubtful.
I still sometimes carry an umbrella. Pre-war example with a silver band.