Hi Atlantia,
I believe La Modediza to be one of the Tandil-based factories that has been producing factory cutlery since the mid-century. I would think yours dates from ca. 1950-1960. While not necessarily rare nor unusual, these provide a nice study of form of the ubiquitous knife type traditionally associated with the Gaucho culture (I have one myself from another Tandil manufacturer), and while not all that old are more collectible than contemporary examples to be sure.