Rick,
One version is in the DT, just CLICK HERE. I searched under [one wore blue and one wore]. I didn't add "gray" because of the spelling question (is it grey?).
This version was song by multitudes of folk oriented artists in the late 60's and early '70's. Of course, nothing folk (traditional) about it, a composed ditty.
The song that Harpgirl mentions was the subject of a recent thread and lyrics are there. Just CLICK HERE to find that.
Enjoy the song, whichever it is.
Roger in Baltimore