I know this thread is 5 years old but I'm now working on the song for my next book. Having had a good look at all 11 versions in Greig-Duncan it's clear that the above 26 stanza version is based on something else. The Scottish versions are pretty consistent and have extra stanzas. It seems pretty clear to me that these Scottish versions and the 1790s version are based upon something earlier. This is partly evidenced by the garbled commencement to the older version. If pushed I'd say, although the voyage doesn't commence in Scotland, it's highly likely that's where the ballad originated, probably Edinburgh or Falkirk or Stirling which all produced many chapbooks in the 18thc.

There are not really many oral versions of the later Canada I O variant, a handful in southern England and about the same in North America.

I'm aware of Nic Jones' influential recording but were there others, Martin Carthy perhaps? Was Nick the first to record it. The only albums of source singers with a version are by George Upton of Sussex.
Malcolm would have answered that in a flash!