Dear Mr. Ozel,
Thank you for posting your request on History Hub!
We searched the National Archives Catalog and located two series of the Joint United States Military Mission for Aid to Turkey (JUSMMAT) titled Centralized Background Instruction Files and Memorandums, 1/1974 - 10/1/1976 in the Records of U.S. European Command (Record Group 531) and the Orders and Investigative Civil and Criminal Case Files, 1969 - 1973 in the Records of Interservice Agencies (Record Group 334) but were unable to locate telegrams about a transfer of a cruiser to the Turkish Navy.
We also located four possible series titled Political-Economic Subject Files, 1961 - 1975; Records Relating to Turkey, 1974; Subject and Country Files, 1964 - 1973; Subject Files, 1960 - 1981; and Records Relating to Manufacturing Licenses and Technical Assistance Agreements, 1950 - 1979 in the General Records of the Department of State (Record Group 59). For access to these records, please contact the National Archives at College Park - Textual Reference (RDT2) via email at email@example.com.
In addition, there are NATO-Related records at Naval Historical & Heritage Command that may mention the transfer.
We hope this is helpful. Best of luck with your research.