The version in O Lochlainn is very similar.

PEGGY BAWN

As I ga'ed o'er Hielan' hills to a farmer's house I came.
The night being dark and something wet I ventured in the same,
Where I was kindly treated and a pretty girl I spied,
Who asked me if I had a wife but marriage I denied.

I courted her the lee long night, Till near the dawn of day,
When frankly she to me did say, "Along wi' you I'll gae;
For Ireland is a fine country, And the Scots to ye are kin:
So I will gang along with you, My fortune to begin."

The morn being come and breakfast o'er, To the parlour I was ta'en;
The gudeman kindly asked of me, If I'd marry his daughter Jane.
"A hundred crowns I'll gi'e with her, Forbye a piece of lan';"
But scarely had he spoke the word When I thought of Peggy Bawn.

"Your offer, sir, is very good, And I thank you too," said I,
"But I cannot be your son-in-law, And I'll tell you the reason why:
My business calleth me in haste, For I'm the king's servant bound,
And I must gang awa' this day, Straight to Edinboro' town."

O, Peggy Bawn, you are my own, Your heart lies in my breast;
And though we at a distance are, Yet I love you still the best:
Although we at a distance are, And the seas between us roar,
Yet I'll be constant, Peggy Bawn, To you for evermore.


#5 from More Irish Street Ballads, by Colm O Lochlainn (1965, Three Candles, Ltd. - 1978 Pan Books edition)