More valuable mediumwave info from fellow DXers in Argentina:

From Argentina en AM y FM:
(Google translate)
Argentina and Peru, are the only two countries of the Southern Cone of America that own operational stations in the expanded Modulated Amplitude Band (1610-1710 KHz), even our country has awarded several seasons in that segment of the dial, although most of them are currently without airing and other long inactive. During this year 2021, the reduction in the number of audible stations in that extended sector of the dial is very noticeable, with many stations being stopped operating for the reasons we were referring to in previous articles.
Here is the list of stations active at the end of May 2021:
1610, Magic Radio (Laboulaye, Cordoba), Radio Light of the World (Rafael Calzada, Buenos Aires)
Radio Sentires (Merlo, Buenos Aires)
1620, Radio Italy (Villa Martelli, Buenos Aires)
1620, AM 16-20 Radio (Mar del Plata, Buenos Aires)
1620, Radio Mitre (Cañada de Gomez, Santa Fe)
1630, LRI234 Radio America (San Jose, Between Rivers)
1650, Radio A (Adrogué, Buenos Aires) – TESTING
1660, LRI232 Radio City of Nogoyá (Nogoyá, Between Rivers)
1660, Radio Revivir (Gregory of Laferrere, Buenos Aires)
1710, Radio Jungle (Ituzaingó, Buenos Aires) 
Mika DX Makelainen to FB group (2021-05-23)