; of which $681,441,500 shall be available until September 30, 2020; and of which such sums as become available in the Customs User Fee Account, except sums subject to section 13031(f)(3) of the Consolidated Omnibus Budget Reconciliation Act of 1985 ( 19 U.S.C. 58c(f)(3) ), shall be derived from that account: Provided , That not to exceed $34,425 shall be for official reception and representation expenses: Provided further , That not to exceed $150,000 shall be available for payment for rental space in connection with preclearance operations: Provided further , That not to exceed $1,000,000 shall be for awards of compensation to informants, to be accounted for solely under the certificate of the Secretary of Homeland Security. Procurement, construction, and improvements For necessary expenses of U.S. Customs and Border Protection for procurement, construction, and improvements, including procurements to buy marine vessels, aircraft, and unmanned aerial systems, $5,510,244,000, of which $462,022,000 shall remain available until September 30, 2021, and of which $5,048,222,000 shall remain available until September 30, 2023. U.S. immigration and customs enforcement Operations and support For necessary expenses of U.S. Immigration and Customs Enforcement for operations and support, including the purchase and lease of up to 3,790 (2,350 for replacement only) police-type vehicles; overseas vetted units; and maintenance, minor construction, and minor leasehold improvements at owned and leased facilities; $7,333,079,000; of which $6,000,000 shall remain available until expended for efforts to enforce laws against forced child labor; of which $33,700,000 shall remain available until September 30, 2020