The For Ever brand belongs to the Bolognese company "Ditta Ivo Germano", that registered it in 1954 (Reg. Gen. N. 115909). The production of pens marked "FOR EVER" and "FOUNTAIN-PEN" (on two lines) however was on the market at least from the 20s, with safety and overlays models. The activity of Ivo Germano is brought back, according to Letizia Jacopini, to the "La Stilografica" store in via degli Orefici, which he founded and then was carried on by his son Gianstefano Germano.
The For Ever fountain pens are considered, according to the Emilio Dolcini analysis in his Omas book, mostly a production commissioned to Omas although Letizia Jacopini points out the possibility, especially for safety and overlay pens, whose style and processing does not correspond to the Omas one, that productions could have be done by others. But some sample of Omas and Minerva rebranded Germano pens have been found, as also, less common, some rebranded Ivo or La Stilografica Bologna, confirming without possibility of denial the Omas production in favor of Germano.
The link with Omas is further confirmed by the registration in 1941, two years before the similar recording made by Armando Simoni, of the Permanio brand (Reg. Gen. N. 64310), just for "a metal alloy particularly suitable for the construction of nibs for fountain pens". It is unclear whether the trademark has been sold, although this seems to be the most likely hypothesis, considering the relationship between the two companies.
References: "La storia della Stilografica in Italia" by Letizia JacopiniAvailable material: