I've found another version of "The Cowboy's Lament" with the "Montana" stanza in it in James F. Leisy, The Folk Song Abecedary (Hawthorn Books, 1966, pp. 69-70), though this, "as sung by Slim Critchlow of Berkeley, California," seems to be a later one. The tune is that of the Larkin version.

THE COWBOY'S LAMENT (second version)

1. So early one morning I rode o'er the ranches,
So early one morning I rode over there
I spied a young cowboy, so brave and so handsome
With coal black eyes and wavy black hair.

2. His eyes were fast glazing and death was approaching,
His white lips were curled and tortured with pain,
As he spoke in a whisper of a scene far behind him,
Of his home in Montana he'd ne'er see again.

3. "Oh, beat the drum slowly and play the fife lowly,
Play the dead march as you carry me along;
In the grave throw me and roll the sod o'er me,
For I'm a young cowboy and I know I've done wrong.

4. "My home's in Montana; I wear a bandana,
My spurs they are silver, my horse is a bay.
I first took to drinking and then to card playing,
Which brought me to trouble, I'm dying today.

5. "Let sixteen gamblers come and carry my coffin,
Let sixteen cowboys come and sing me a song.
In the grave throw me and roll the sod o'er me,
For I'm a young cowboy and I know I've done wrong.

6. "Wrte me a letter for my gray-haired mother,
And break the sand news to my sister so dear.
But not one word of this shall you mention
When a crowd gathers 'round you my story to hear.

7. "Oh, there is another, more dear than a sister;
She's lovely and pure as the dew on a rose.
Tell her to wait for her lover no longer,
For he sleeps where the prairie wind smoothly blows.

8. "Tell her her image has always been with me,
Carrying me up through the long, lonely days;
And that I'm taking it down through the valley,
Locked in my heart to be with me always.

9. "Then swing your rope slowly and rattle your spurs lowly,
And give a wild whoop as you carry me on.
Take me to the green valley and lay the sod o'er me,
For I'm a young cowboy and I know I've done wrong.

10. "Oh, bring me a cup of pure, pure water,
A cup of pure water," the poor fellow said.
But when I'd returned his soul had departed
Anf gone to the Giver; the cowboy was dead.

11. We beat the drum slowly and played the fife lowly,
And bitterly wept as we bore him along;
For we all loved our comrade, so brave, young, and handsome;
We all loved our comrade although he'd done wrong.

~Masato