Where, after payment of tax by the manufacturer, a firearm is exported, and satisfactory proof of exportation (see Sec. 479.118) is furnished, a claim for refund may be submitted on Form 843 (see Sec. 479.172). If the manufacturer waives all claim for the amount to be refunded, the refund shall be made to the exporter. A claim for refund by an exporter of tax paid by a manufacturer should be accompanied by waiver of the manufacturer and proof of tax payment by the latter.