Below is the version collected from George Blake of Hampshire by Dr. George Gardiner, and it can be found on my CD - George Blake's Legacy (on Forest Tracks).
Blake's tune was a version of "The Marigold" or "Star of County Down".

Tim Radford

THE ROCKS OF SCILLY.

It's of a brisk young seaman bold that ploughed the raging main.
Come listen to my tragedy, while I relate the same.
It's pressed I was from my true love, She's the girl that I adore,
And sent I was to the raging seas, where the foaming billows roar.

We had not sailed a league on sail before a storm did rise,
May the Lord have mercy on our souls, so dismal was the skies.
Sometimes aloft, sometimes on deck and the other time below,
When the thoughts of my Polly love run in my mind when the foaming billows roar.

Our Captain being a valiant man he on the deck did stand
Here's a full reward of fifty pounds for the first that could see land.
Then up aloft our boatswain went on the main topsail so high,
He looked around on every side, neither land nor life could spy.

The very first time our ship she struck so loud against a rock,
May the lord have mercy on our souls for the deep must be our lot.
And out of eight hundred seamen bold only four got safe on shore,
Our galliant ship to pieces went and she was never seen any more.

And when the news to Plymouth came, our galliant ship was lost,
Caused many a brisk young seaman bold for to lament her lost.
And Polly dear she must lament for the loss of her sweetheart,
'Twas the raging seas and the stormy winds caused my love and I to part.