Liquid/Gel dispensers that charge based on quantity dispensed.

I am trying to find a something that will dispense a lotion in the same way that a gas pump does. Simply swipe your card or insert money and use until you have enough.

I am having a lot of trouble finding this through internet searches so I was wondering if anyone could point me in the right direction.

Edit: I am willing to try to get it manufactured myself if necessary. What I am looking for will need to be customized in the end regardless. I just need a good starting point.

from Liquid/Gel dispensers that charge based on quantity dispensed.