Here's how I wrote it down back in 2002, but it appears to date from the 1970s or '80s

SHANTYMEN BOLD
We're Shantymen bold with voices like thunder;
We half-inch four capstans, haul halyards and sheets.
Each week we take ship in The Four-masted Clipper:
That's a neat little boozer just down Gasworks Street.

Chorus:
We rant and we roar like true British sailors.
We rant and we roar all night in the pub.
Like true shellbacks born who've been twice round the Horn,
We get half-seas over each week at the club.

Our landlord became owner with a big win from Vernons,
And to see his wife work at the pumps is sublime.
But before he was skipper of The Four-masted Clipper
He commanded the pride of the Red Barrel Line.

We've sung of storms off Cape Horn and gales up in Greenland,
But if, when we're leaving, rain falls from the sky,
Each stout-hearted fella' puts up his umbrella
Or phones for a taxi to get him home dry.

We've sung on the Victory in dry dock at Portsmouth;
On the Cutty Sark, likewise, we've all done our thing.
But when we go to Greenwich we go by the tunnel:
If we used the ferry we'd be too sick to sing.

Now progress has made all this hard work redundant,
But as long as we're here these fine songs shall not die
In The Four-masted Clipper with a pint in your flipper,
Where the hardest work's draining each full tankard dry