§ 64. Contracts for dies, plates and engraving. The state comptroller shall have power and authority, and it shall be his duty, to enter into and execute for and on behalf of the state such contract or contracts for dies, plates and engraving necessary for the preparation of bonds, notes and certificates of indebtedness at such time or times as it shall be necessary for issuance thereof. Such dies, plates and engraving shall be prepared and completed under his supervision and he shall be the custodian of all dies, plates and other material required in the preparation of such bonds, notes and certificates of indebtedness.