Effective October 1, 1989, the entire costs (excluding salaries of the United States military personnel other than the Coast Guard) of overseas management of international security assistance programs under this section shall be charged to or reimbursed from funds made available to carry out this part or the Arms Export Control Act [
22 U.S.C.
2751 et seq.], other than any such costs which are either paid directly for such defense services under section 21(a) of the Arms Export Control Act [
22 U.S.C.
2761
(a)] or reimbursed from charges for services collected from foreign governments pursuant to section
21
(e) [
22 U.S.C.
2761
(e)] and section
43
(b) [
22 U.S.C.
2792
(b)] of that Act.