By chance I found a cheap 5CD set on eBay last month, called Folk Songs and Ballads with Woody Guthrie, A.L. Lloyd, Ewan MacColl, Margaret Barry and Susan Reid. The Lloyd / MacColl tracks are the 9th volume of the 8LP Riverside set mentioned above, Great British Ballads Not Included in the Child Collection. There aren't any liner notes or sourced mentioned though; but as far as I know this is the first CD issue of these tracks.

Reinhard