The Secretary shall direct the vocational rehabilitation of permanently disabled employees and shall arrange with the appropriate public or private agencies in States or Territories, possessions, or the District of Columbia for such rehabilitation. The Secretary may in his discretion furnish such prosthetic appliances or other apparatus made necessary by an injury upon which an award has been made under this chapter to render a disabled employee fit to engage in a remunerative occupation. Where necessary rehabilitation services are not available otherwise, the Secretary of Labor may, in his discretion, use the fund provided for in
section 944 of this title in such amounts as may be necessary to procure such services, including necessary prosthetic appliance or other apparatus. This fund shall also be available in such amounts as may be authorized in annual appropriations for the Department of Labor for the costs of administering this subsection.