I have an Akubra Stylemaster in which the waterproofing treatment has broken down and now it can't hold up to rainfall any more.
Do you consistently wear fur felts until they are soaked through? How much time in the rain are you talking about. It takes a bit to soak through a stiff felt and softer ones won't soak through in a flash. At least in my experience. If so, you may need to consider different hat materials for whatever you're doing.
I recently left a NOS Bailey cowboy hat out in the rain for almost two days to rid the black hat of over dye. I regularly checked the hat and it took quite some time for it to soak through and it never lost most of the shape I put in it. I mention this only because I don't know how long my hat would stand up to that sort of (ab)use, but I know if I dried it carefully which I did, it would stand up for more.