I once had a splendid album (vinyl) which had on it among other things his own "So long" and Paxton's "Rambling Boy" (in which he changed the chorus line from "Here's to you..." to "Fare thee well..." which worked much better, or at least was better suited to his own style). I still have a tape of it somewhere, but can't remember what the album was called. I think it came out around 1966-67 so not likely to have been his earliest.