Here are four more Missouri Pacific blotters from the Dale Hastin collection. They all have the “Service Institution” slogan and none mention the Eagle streamline, which was inaugurated in 1940, so I suspect they are from before 1940.
Other than the message that “All Principal Trains [Are] Air Conditioned,” the blotters do little more than give an impression of service, so there is not much I can say about them either other than click on any image to download a PDF of the blotter.