1) Colombians proudly assert that they were the ones who claimed and got
the "banda internacional de los 62 metros" going. I think there is something to it.
2) I´m afraid you are a bit late in researching something which has gradually been
going down the drain. See some background and future predictions, which alas
have come true, in my 1987 book "Latin America by Radio".
A few decades ago there were plenty of portables around in most of Latin America.
Some of the receivers which covered the 60 and 90 metre bands were not for
sale in Europe.
In Ecuador, you would often see Quichua Indians carry king size portables, "the poorer
the Indian, the bigger his portable". But even modest family homes would afford a
decent table top receiver.
If you wish to look into what kind of receivers people were using in Latin America
decades ago there are interesting web pages featuring vintage receivers, for instance that of
Radio Fides, in Bolivia, http://www.radiofides.com
Another interesting page is that of Brazilian collector João Mello, editor of
"Antique Radio News". See http://www.bn.com.br/radios-antigos/evento.htm