Blomman, there is a very nice chapter (VII) about this line (Ranchero) in the "Omegamania" which was the auction book published by Antiquorum. Please note it is a very good reference for vintage Omage collection, but i found some of the watches's dial were refinished!
in that chapter, they displayed 5 Ranchero for that auction. all case reference is 2990 with 36mm of the size in diameter. the movements are either Cal.267 or Cal.268 which both are famous 30mm calibre.
apart from these, the book also mentioned that the Ranchero can be available with sub seconds and centre seconds. and rarely with both sub second and centre seconds. the cases were in SS, steel and gilt, or sold gold. the dails were most commonly black or white with large luminous markers and luminous "Dauphine", "Alpha" or "Broad Arrow" hands; the gold-cased watches were more of a dress than sports watch, so they had a dial with applied gold markers and gold hands.
like other vintages, must do homework before committing to buy a watch, especially this model. as fas as i know, there are lot of redone or repainted dial with wrong hands as well available out there as the one you posted here.
hope it helps.
stefan