Refunding bonds may be made payable from any taxes or pledged revenues, or both taxes and such revenues, which might be legally pledged for the payment of the bonds being refunded at the time of the refunding or at the time of the issuance of the bonds being refunded, as the Commission may determine, notwithstanding the taxes, or the revenue sources, or the pledge of such revenues, or any combination thereof, for the payment of the outstanding bonds being refunded is thereby modified, subject to the provisions of NRS 349.320.