Dear Mr. Phillips,
Thank you for posting your request on History Hub!
We searched the National Archives Catalog but were unable to locate information on ships leaving New York and arriving in Buenos Aires in 1905.
FamilySearch has a webpage on Emigration and Immigration in Argentina that may be helpful to your research. At the bottom of the page are several links to databases for ship records. There are immigration records for Argentina located at the Family History Library in Salt Lake City, Utah.
Another genealogy site has lists of ships that arrived in Buenos Aires from 1882-1960, and some of the corresponding passenger lists.
If you know the names of any passengers who may have arrived in Buenos Aires on December 7, 1905, we suggest you search the Centro de Estudios Migratorios Latinoamericanos (CEMLA) ship arrivals database and/or contact The National Archives of the Republic of Argentina, Departamento Archivo Intermedio.
We hope this is helpful. Best of luck with your research!