The Tax Court is authorized to make such expenditures (including expenditures for personal services and rent at the seat of Government and elsewhere, and for law books, books of reference, and periodicals), as may be necessary efficiently to execute the functions vested in the Tax Court. Notwithstanding any other provision of law, the Tax Court is authorized to pay on behalf of its judges, age 65 or over, any increase in the cost of Federal Employees' Group Life Insurance imposed after the date of the enactment of the Pension Protection Act of 2006, including any expenses generated by such payments, as authorized by the chief judge in a manner consistent with such payments authorized by the Judicial Conference of the United States pursuant to section 604(a)(5) of title 28, United States Code. Except as provided in section 7475, all expenditures of the Tax Court shall be allowed and paid, out of any moneys appropriated for purposes of the Tax Court, upon presentation of itemized vouchers therefor signed by the certifying officer designated by the chief judge.