Hunting around I found a list of the contents of the special collection Paisley University Library has of the papers of the late Norman Buchan, who was a great folk music enthusiast as well as an MP - here is a page on Dick Gaughan's website about him. (God, we could use him today!)

Anyway, one of the items listed is "File 13 - Landmarks - scripts for radio programme".

So if anyone's in a position to chase this up it could be worth doing.