WD19 Thunderbolt replacement cable module part number

Hi. I am struggling with Dell Support in Brazil to acquire the replacement thunderbolt replacement cable module for WD19. Can anyone point me the part number so I can call sales department and request this part? I have a WD19 USB-C Dock Station and wish to acquire the Thunderbolt module to be able to use it with Thunderbolt devices. I have a Dell P2415Q attached to the WD19 using Display Port, and cannot use UHD 3840 x 2160 in 60Hz. 

Any help is highly appreciated.

Thanks!