Metal hydride tanks prices can be calculated from the amount of MOC (material of construction) required. For instance, if want to carry 5 kg of LaNi5 alloy, you have to design a reactor which can contain atleast 12 kg of the alloy (considering 0.5 porosity and 20% of expansion volume). Now, the amount of MOC can be evaluated from density of the MOC multiplied with volume of MOC. Now just multiply per kg price of that material with this.