If price is really important then I make my own sensors from IC's bought through electronic supply houses. The IC's are really cheap.
My original C&H ignition for my BME 50 needed a sensor while C&H was in limbo a few years ago. So I just JB welded an IC to a scrape piece of alum and made my own. It helped me years later because it taught me the standard pin outs on the IC's.