Not sure from the picture but it might be this one?
https://www.te.com/usa-en/product-176273-1.html?q=+AMP+UNIVERSAL+POWER+PLUG+4P&source=header
Can you look closely to see if there is anything written on the plug. eg numbers, molex or amp etc.
I think someone wanted this years ago, anyway here it is again. I did work many years ago don't know if it still does. I think it will work with monitors up to 20"
Found one! Has no output. High rectified mains across the main filter caps. Tried to fix it many years ago but just has sat in a box. Yours if you want it.