There is authorized to be appropriated, out of any money in the Treasury not otherwise appropriated, such sums as may be necessary to carry out the provisions of this subchapter, which shall not exceed the sum of $8,572,000 to be available for all expenses incident to the examination and establishment of the said Colonial National Historical Park and for the acquisition of lands and/or lands and improvements needed for the completion of the park, including the securing of options and other incidental expenses. The area of the Yorktown battlefield, authorized for inclusion in said park, is extended to not to exceed four thousand five hundred acres, and all Government-owned lands within the boundaries of said park as established by presidential proclamation, except those determined by the Secretary of the Interior as not necessary in carrying out the objects of said park are transferred to the administrative jurisdiction and control of the National Park Service.