Lisa normally specialises in women's head-wear, but I think she may now start a range of hats for men as a result of this request from me. I hope so. I told her about the forum I came upon when searching for it off the web-peg, and on it, people are discussing how to get hold of a hat like Rathebone's, and how impossible it seems to be. Someone found (as I did) a similar one from Bates and Co of London, but this has been discontinued for reasons only known to Bates.
Here is a link to Lisa's website: http://www.lisaburrows.com/
Pay her a visit - you never know, you may need a good hat one day.