When canning, I always use jars with a two piece lid- a metal ring, which is reusable, and a flat metal top with a rubber sealer mounted on it.
These rubber sealer plates are only used once.
The actual jar makes no difference at all, as long as your lid fits the threads properly.
The heating in boiling water causes a vacuum to occur in the jar, and the rubber washer seals the lid tightly- this is what keeps bad bacteria and growing things out.
http://www.pickyourown.org/canningjars.htm
There are also jars with metal wire clamps that hold glass lids on, but these are very hard to find in the USA these days- you mostly see them on very high end european foods.
here is more what you are looking for-
http://articulo.mercadolibre.com.ar...hermeticos-kilner-jar-ingleses-excelentes-_JM
you might try asking these guys-
http://www.mil-envases.com.ar/index.php
house of 1000 jars- they ought to know who sells them if they dont.
I have found that due to the vagaries of Industria Argentina, its much less intuitive and simple to just google stuff here-
even things like todar.com.ar tend to have a lot of gaps.
Many many companies dont bother to have websites, or are solo mayor, or just still operate like they did 50 or 100 years ago.
So, when trying to find things, you can just sit at home in your underwear and type. You need to actually go out and talk to people, or, at a minimum, call em on the phone and talk. In person is better, though- they take you more seriously that way.
There is usually, in Argentina, a series of old family owned businesses that make most anything- but they take tracking down.