This can be stated in active form. Alternate translation: "Use funds from the king's tribute beyond the river to pay these men" (See: [[rc://en/ta/man/translate/figs-activepassive]])
"The king's tribute" refers to taxes that people pay the king. Alternate translation: "Money from the taxes that you collect for the king from the people beyond the river" (See: [[rc://en/ta/man/translate/figs-explicit]])