Has anybody ever though of buying bulk natural coconut charcoal from a manufacturer?
Kamado is a good example
Apparently you can get a 12lb box for a shipped price of 14.99
That is just an example and the pieces offered would need to be cut down to be usable on the hookah but there are other companies that make everything from coco-nara sized pieces to gigantic grilling monsters the size of dinner plates.
Considering what they are it seems that this might be a worthy endeavor or at least experiment.