I'd never heard of them, but after spending a pleasant online 15 mins or so checking them out, I reckon there might be one half way up a silver birch tree in my sister's back garden. We've been going down there (she lives in the same village) whenever the icy wind lets up, to get a change of scene.
It's so weird sitting well apart & not being able to go in the house.....
Thing is do I risk death by trying to get it down, or miss out on the chance to live forever. I notice its name in French is champignon de l'immortalité. Maybe stepladders & a pole.
Have you tried it & what does it taste like? I suspect straight off the tree & lightly boiled for a few hours it tastes worse than shit, but what's to lose.
Way, way, back in time I did the same thing with
amanita muscaria in hopes of a glimpse of a different sort of immortality. Just remembering what that tasted like makes me want to puke still.