I think the verses are a P&O version of the M.V. Hardship song. As with most M.N. songs there's no definative version. Besides the version I know, there's also a version about Harrisons of Liverpool.

As I was a'walking down by K.G.V.
I saw an old tramp ship tied up alongside
The M.V. Hardship that were her name
She was bound out to Kiwi & back home again
CH   Pound away, pound away, from London to Kiwi's a hell of a way.

Sailded down the channel on a cold frosry day
Then rounded Ushant & south 'cross the Bay
The 2nd Stewards 'fruit' & the cook he is too
They bugger each other & poison the crew

There's nothing for dinner, there's nothing for tea
But that fat cook he keeps winking at me
Him & the steward are a bloody disgrace
Just see the look on the galley boys face

The 2nd's a drunkard, we've a bastard as Mate
The Bos'un does nothing but dream about work
As for the Old Man well we cannot say
'Cause no bugger's seen him since sailing day

When we got to Kiwi we all went ashore
Off to Ma Gleeson's to get us a whore
But when we got there the pickings were poor
'Cause the P.S.N.C. lads had got there before

Now the voyage has ended in West India Dock
To Charlie Brown's with our pay off we'll flock
Soon we may sign with Ropners or Ben
But the M.V. Hardship won't see us again.

I got this version [I think ] when aboard the M.V. King James in 1972. I have about a dozen other M.N. songs, if anyone is interested