You can now get these without spending a lot, Divine Sap drops as is, from ANNM in Batallia Downs/Jugner Forest, along with a lot of good drops, so people tend to spam it. Going for 20k now on Kujata.
Ofcourse then you have the divine sap, which is made from divine log. which makes this a very expensive 5 min of regen and refresh. Still wanna do this, trade Libation Abj and cursed beverage to Alphollon C Meriard in Northern San d'Oria to turn this into Amrita. Libation Abj can be obtained from various NM's in sky as well as from some BCNM's, can also be bought from Dabih Jajalioh in Ru'Lude Gardens for 250,000 Gil.