The Secretary of the Interior is authorized, in his discretion, to acquire in behalf of the United States, through donations or by purchase at prices deemed by him reasonable, or by condemnation in accordance with section 3113 of title 40, lands, buildings, structures, and other property, or interests therein, located within the boundaries of the Chalmette Unit of the Jean Lafitte National Historical Park and Preserve as fixed and determined by this subchapter, the title to such property and interests to be satisfactory to the Secretary of the Interior, and to accept donations of funds for the acquisition and maintenance thereof: Provided, That payment for such property or interests shall be made solely from donated funds.