Size Eur 39 C - UK size 6 / US 8.5 with standard width according to Bally's size guide 

Heel measures 6-6.5 cm

Please not this is a vintage shoe and may be slightly smaller than modern sizes, I have taken some measurements to hopefully help

Length of sole 25.5cm

Across Sole at widest part of foot 8.5 cm

Please message if you have any questions