Vintage Penny’s Marathon Straw Boater Hat

Belonged to my father in law. Around the 1960’s. The outer part of the hat is in excellent condition. No stains or damage. The inside rim of the hat has lost all of its foam. It’s disintegrated with age. There’s some staining to the inside upper part of the hat. Never would show while wearing! Also the strap could be freshened up! I’m unsure how to clean it. This is a really cool vintage Penny’s Marathon boater hat. They didn’t smoke so clean home! Size 7 oval long.