Connect POS System/Card Reader to Power Bank Station

Attached is a picture of my PowerBank station (without the card reader), and what we want our station to look like (with the card reader). We offer PowerBank station rental services where if you want a PowerBank you purchase it through an application and a PowerBank comes out. What we want to integrate is a card terminal/pos system onto the station allowing any user to use their physical credit card to get a PowerBank. Similar to a vending machine (you pay and a drink comes out). We have distributors in China but we want to find someone in the UK who knows how to integrate a card reader into our station for cheap. We could potentially higher that expert permanently.