The version my grandfather sings is:

If her drawers are navy blue, thats Peggy O'Neill
If she takes them down for you, thats Peggy O'Neill
She may charge a tenner, she may charge five bob
It all depends on the size of your knob
Some think it's better to use a french letter
On Peggy O'Neill

Don't know the rest but would love to get the full version.