(2) If the agreed means or manner of payment fails because of domestic or foreign governmental regulation:
(a) The lessor may withhold or stop delivery or cause the supplier to withhold or stop delivery unless the lessee provides a means or manner of payment that is commercially a substantial equivalent; and
(b) If delivery has already been taken, payment by the means or in the manner provided by the regulation discharges the lessee's obligation unless the regulation is discriminatory, oppressive or predatory.