(Conference report filed in House, H. Rept. 94-529) Maritime Appropriation Authorization Act - Authorizes appropriations for fiscal year 1976 to the Department of Commerce for: (1) acquisition, construction, or reconstruction of vessels and for construction-differential subsidy; (2) payment of obligations incurred for operating differential subsidy; (3) research and development; (4) reserve fleet expenses; (5) maritime training at the Merchant Marine Academy; and (6) financial assistance to State marine schools. Authorizes supplemental appropriations for fiscal year 1976 as may be necessary for specified expenses of the Merchant Marine Academy. Provides that not less than 10 percent of any funds appropriated for construction differential subsidy and operating differential shall be allocated to each range of ports, consisting of the Atlantic, Great Lakes, Gulf, and Pacific ranges. Requires annual reports from the Secretary of Commerce to the Congress on actions to assure that direct and adequate service is provided by United States-flag commercial vessels to each such range of ports. Increases the statutory limitation on Federal ship mortgage guarantees to $7,000,000,000.