Hi,
This occurs as the title and in the lyrics of a song by Bruce Springsteen. Note there is no comma.
I though I heard the Captain say,
Pay me my money down,
Tomorrow is our sailing day,
Pay me my money down
Oh pay me, oh pay me,
Pay me my money down,
Pay me or go to jail,
Pay me my money down
It seems to be an emphatic way of saying 'Pay me my money!'
I've never heard it, and I wouldn't say it's a common expression at all.
Best wishes, Clive