I think you may have hit on something there. A military issue roadster. These bikes have the chainwheel, single speed, lack of brazed on pump stays and seat post in common with your bike. They don't have the Raleigh thimble forks though. The pedals with the reflectors began in the late 60s. The other one is older. No idea what an original would look like. You might be able to get some dating information from the rear hub.