What is Kerguelen cabbage, and where can it be bought?

"'Pringlea antiscorbutica' is a plant which looks somewhat like the common cabbage and belongs to the same family (Brassicaceae). It was named after the island of its discovery, Kerguelen Island, and its Latin name derives from Sir John Pringle, President of the Royal Society at the time of its discovery by Captain James Cook's Surgeon, William Anderson in 1776."

https://en.wikipedia.org/wiki/Pringlea_antiscorbutica

"The species grows on Heard Island, the McDonald Islands, Crozet Islands, Prince Edward Islands, Marion Island and Kerguelen Island. These remote islands are at roughly 50º South Latitude, constantly buffeted by strong winds. This makes pollination by flying insects impractical, explaining why the Kerguelen cabbage is self-pollinating."

http://www.absoluteastronomy.com/topics/Kerguelen_cabbage

It is certainly not on sale at my local farmer's market!

Here's a '98 study on the stuff:

1998 -- The Kerguelen cabbage has shown so far that it will grow well in Australia and that it has commercial potential.

https://www.anbg.gov.au/gardens/research/hort.research/sub-antarctic/article3.html