Well after many hours of perusing the world wide web, I've concluded that this might be a 'badged' L.O. Dietrich Vesta Model CEK (see pic, upper right hand machine... the CEK model has the tension on the face plate, whereas the model CEG has the tension on the front). In the Rojano pics above, it's not visible but, on the arm it has a CE decal (could that stand for the Vesta CE model??). Also many of the Vesta models seem to have the same (or very similar) striated design on the chrome pieces (faceplate, etc), a marbled type of effect. Plus I ran across a Vesta Sylvia that had a very very (if not the same, not sure due to size/angle of pic) similar lion decals on it. So for now, I'm thinking this could be a L.O. Dietrich 'badged' Vesta that was exported to Argentina, until the mystery unfolds further insight.