Can't help with that song but thought I'd contribute my memories of Don- he found fame via the Eamonn Andrews show in 1968- I remember that because I worked for Thames TV at Teddington at the time. I was also involved with the Marsden folk club in South Shields & well recall the night we had him booked for the Sunday night club.
He was on 'Top of the Pops' on the Thursday as he was No 4 in the charts with 'Rosie' at the time but he did turn up for his £12 or whatever it was, having travelled many a mile to do it... Just as well as the queue was twice round the pub AT 7PM!
Many years later (c2005?) I was at the Seaford folk club at the old 'Wellington' pub & was told Don was in the back bar. I was delighted to see him again- he said he didn't busk London any more- too much hassle up there, but he did busk the country towns like Horsham & Lewes.... I complimented him on having done the Marsden when he could have named his price at Newcastle City Hall that night... 'well, you was mates, wasn't you' he said- a comment which about sums up the kind of decent bloke he was...... RIP Don