I'll throw in a few of my favourites of the time that haven't been mentioned yet (limiting myself!)

The Dransfields: The Rout Of The Blues
Louis Killen: Ballads and Broadsides
Dick Gaughan A Handful of Earth

and some of the North-Eastern ones:
Along The Coaly Tyne
Jack Elliott of Birtley


and for a taster of a lot of traditional singers the two Topic records from the Folk Songs of Britain series:
The Child Ballads, vol1 & 2


(And I always had a fondness for The City Waites - historical rather than traditional maybe, but with some songs you'll recognise from the tradition: The City Waites or A Goreous Gallery of Gallant Inventions).


Mick