I had a quick google search for Peter Kennedy and if you check his archive in The British Library website you should be able to find out if the recordings are available to listen to (obtain copies?)
Also if you note the Topic and other records you might be able to find them to buy on a second hand records site? (I have used a couple, need to find the names of the shops/dealers again....or someone on Mudcat will know!)
It is also possible tgat tge Scottish recordings might be on Tobar an Dualchais (spelling?)/ Kist o' Riches,
which is the School of Scotish Studies' archive, gradually being built up.