The following funds shall be deemed an indebtedness to the United States of the particular insurance fund involved, and the Secretary is authorized and directed to pay the amount of such indebtedness to the Secretary of the Treasury, with simple interest thereon from the date the funds were advanced to the date of final payment at a rate determined by the Secretary of the Treasury, taking into consideration the average rate on outstanding marketable obligations of the United States from the date the funds were advanced until the date of final payment—
((1)) funds made available to the Secretary pursuant to the provisions of sections 1705 and 1708 of this title, exclusive of amounts heretofore refunded, (a) for carrying out this subchapter and with respect to mortgages insured under where such funds were credited to the general reinsurance account in the Mutual Mortgage Insurance Fund, and (b) for the payment of salaries and expenses with respect to mortgage insurance under sections 1713 and 1715a of this title where such funds were credited to the Housing Insurance Fund;
((2)) funds made available to the Secretary pursuant to sections 1737 and 1748a of this title; and
((3)) funds made available to the Secretary by the Secretary of the Treasury pursuant to section 1747i of this title.