Both the legendary gems (Pictured above) and the enchant that adds a meta socket can be bought back in 5.2 at this vendor. Why should you care? Because the enchant can be used on any weapon not just the sha touched one.
As a side note it looks like the legendary gems no longer require you to do the questline to purchase however they will cost you 10k gold up from the 8500 if you do the questline. The 10k gold versions can be purchased from the Tier/Valor Point vendor at Nizou Temple.