。
It cost fifty dollars in bank fees to make this money order.
Literal
This money-order [obj-を] make [to-のに] bank [gen-の] handling-fee [subj-が] 50-dollars cost.
為替 (かわせ) means 'money order / exchange' — a financial instrument. 手数料 'handling fee / commission' is a common banking/business term. ~のに here is not the concessive 'even though' but the purpose marker 'in order to / for the purpose of' — 'to make this order, fees of 50 dollars were incurred.' かかる 'to cost / to take (time/money)' is the standard verb for expenses.