Since we have uncertainty I have dug up a couple of photos from the net. I have to say that the first one is remarkably similar to the OP, it is the uniform of a seaman attached to the Naval Inshore flotilla during WWII and it turns out that the chap shown was resident just down the road from the Lady who held the original photo for all those years. Coincidence it may be but as I have been unable to find a Queens messenger uniform which comes close to the one shown My money is firmly on the Naval link. Does anyone concur with this?