For the next two weeks, the Legion Archaeology mount Spirit of Eche’ro is available by starting a quest chain in Dalaran: The Right Path, given out by Dariness the Learned. This quest is only available every 6 months, following the Legion Archaeology quest rotation, which changes every 2 weeks.
The quest leads you to Laying to Rest, which requires you to survey digsites in Highmountain until you acquire 600x Bone Fragment of Eche’ro.