Well, after sitting down with my guitar, a capo and the album - they play it in A flat. Here’s the closest I can get to a something written for piano. Donald Swann was a wonderful accompanist! Words from the album.

MADEIRA, M'DEAR
(Michael Flanders and Donald Swann)

(G) She was young, she was (D) pure, she was (Bm) new, she was (Em) nice,
She was (A) fair, she was (A7) sweet seven- (D) teen.
He was (Am) old, he was (E7) vile, and no (Am) stranger to (Em) vice.
He was (Am7) base, he was (A7) bad, he was (D) mean.
He had (G) slyly inveigled her (C) up to his flat
To (A7) view his collection of (D) stamps,
And he (G) said as he (C) hastened to (G) put out the (A7) cat,
The (Am) wine, his (A7) cigar and the (D) lamps:

(G) Have some (D7) Madeira, m' (G) dear. You really have (A7) nothing to (D) fear.
I'm (Am7) not trying to tempt you. That (G) wouldn't be right.
You (A7) shouldn't drink spirits at (D) this time of (D7) night.
(G) Have some (D7) Madeira, m' (G) dear. It's so very much (A7) nicer than (D) beer.
I (E) don't care for sherry, one (A) cannot drink stout,
And (A7) port is a wine I can (D) well do without.
It's (G) simply a (C) case of (G) chac'un a son (A7) gout
(C) Have some (D) Madeira, m' (G) dear.

Unaware of the wiles of the snake-in-the-grass
And the fate of the maiden who topes,
She lowered her standards by raising her glass,
Her courage, her eyes and his hopes.
She sipped it, she drank it, she drained it, she did!
He quietly refilled it again,
And he said as he secretly carved one more notch
On the butt of his gold-handled cane:

Have some Madeira, m’dear. I've got a small cask of it here.
And once it's been opened, you know it won't keep.
Do finish it up. It will help you to sleep.
Have some Madeira, m'dear. It's really an excellent year.
Now if it were gin, you'd be wrong to say yes.
The evil gin does would be hard to assess.
Besides, it's inclined to affect me prowess,
Have some Madeira, m'dear.

Then there flashed through her mind what her mother had said
With her antepenultimate breath:
"Oh, my child, should you look on the wine which is red,
Be prepared for a fate worse than death!"
She let go her glass with a shrill little cry.
Crash! Tinkle! it fell to the floor.
When he asked, "What in Heaven?" she made no reply,
Up her mind, and a dash for the door.

“Have some Madeira, m'dear” rang out down the hall loud and clear,
A tremulous cry that was filled with despair,
As she fought to take breath in the cool midnight air.
“Have some Madeira, m'dear.” The words seemed to ring in her ear.
Until the next morning, she woke up in bed
With a smile on her lips and an ache in her head,
And a beard in her ear-'ole that tickled and said:
“Have some Madeira, m'dear!”