Interesting read, and definitely educational for me. I'm not sure I'd want to drink it, but I grew up in an era of processed, pre-bagged tea. :)
I actually really like how that Yeongji Mushroom looks! I did a quick search on Amazon, with no luck finding them there, but I did find a bunch of other scary looking things.
I think for that mushroom, you may find the dried chinese variety. Lingzhi is the Chinese name I believe. Finding the actual living fungis may be difficult.