Hi Joe-
Thank you, yes, that is the webpage that I mentioned as being the only place I could find reference to the song. The site lists a bunch of other songs, and this is what is written as an intro to the song list:

"Long Ago Love Songs is a collection of love songs and dancing songs from the past. They are all set in the British Isles, and the periods range from mediaeval to 19th Century. "

I can't find any contact info for the writer of the page, to check with them about where they found the song. But they seem to be saying that it is traditional.

And yes, that's the episode of the show that I watched. I can watch the episode anytime I want on Hulu, so I can hear the song again. I was just hoping that there was an actual recording or something of the whole song that I could access. There is not even a soundtrack from the show available (maybe there will be eventually...it is a new show).