HI.The man you want is Albert, Spanish no English, he delivers 13.000 to me in Gandesa and charges 125€, very nice guy and reliable,lives in Jesus Tortosa.(Good water)
There is another guy also Spanish lives in Bilalba, Jordy, but cant find his number, but he is very unreliable can never tell you when he's coming, same amount but 140€.
If your going to build a cisterna then build a big one, i'd say minimum 30.000ltrs.
All villages have water (Agriculural) free, in Gandesa its below Dia Supermercat, 1000 ltrs at a time, no key required.
As for Mora Flix areas there must be some one over that way that  delivers water, you'll have to ask locally.
Terry.