Never seen the red spathe variety, Evan. I'll ask the Tropiflora guys - Dennis Cathcart will probably plan a trip to S. America to go find it . . . he lives to travel.
Tree fern fiber is from the trunks of tree ferns that have died. It's used as orchid medium, so you can get it from orchid specialists and suppliers online. It's readily available, but the tree ferns are getting scarce so it's not used as much any more - got expensive. Here's my 12ft. tree fern, and its base is what the material used for orchid mounts etc. looks like. Edited to add, Mj, are you using crushed tree fern? I had a stump of one that had died in my garden and cut it up into chunks for orchid mounts a few years ago.