Based on a pure description, a 585 gold pencil by Montblanc can hardly be identified, because several models exist in 585 gold. For a sensible estimate, clear photos should be posted. An engraving like "M-W-E" is mostly an individual initials or company engraving and no model marking. A dating to the 1950s or 1960s appears plausible but should be verified picture-based.