As Homer would have said .... "Doh!" I didn't quote enough of the entry (don't think I noticed the rest of it) which reads as follows:

"In Misc music box in R.I.C. Courtney Library. Words By John Tremayn"

I've tried Googling the names of the singers - other than establishing that Serpell seems to be a longstanding Cornish surname, I've not managed to track anything else down... as you said, Barbara - frustrating !!! The original thread on Cornish songs did cover this one - and suggested that, although the publishers in question still exist, they were unable to track the song down.... more frustration!!