Fred, I would suggest you ask the Keir Hardie Society- www.keirhardiesociety.co.uk, set up a few years ago to honour the great man. An interest in the old ballads would not be surprising as he spent a lot of his life in the town of Cumnock in Ayrshire, in Rabbie Burns country, and they are quite rightly very proud of him there- a bust stands in the town centre.
The Scottish poet Rab Wilson from the nearby ex-mining town of New Cumnock is also a great proponent of the man and is very knowledgeable about him- if you can follow his 'Lallans' emails, I could put you in touch?

Anyone who's been to the Durham Miners' Gala every July will know that as well as the homage to Birtley folk club heroes Jack Elliott and Jock Purdon, the 'Cotia miners banner features a full picture of Hardie on the reverse.