I'm intrigued but not committed. I went to YouTube, listened to Martin Carthy sing it, opened a MIDI file and tried noting the melody. It seems to work well in 6/4 time (no pick-up note).

The old-timers sometimes did a trick where a tune in 6/4 moved to 3/2, usually towards the end. Thus you hear:

la la la   la la la
la la la    la la la
BAM    BAM    BAM
done!

Listen for that to see if it occurs in this song.