Hi, all the software are bound to specific serial number; we have no public software to send you. Actually, your DS708 is still in free update period, so please refer to page 82 in the user manual to download software.
What kind of USB cable you want? What is it for?

 If you didn't copy your old software  and make a backup of your old software you will not be able to get the old versions back to copy on anew SD card. You need to have the latest version of DS 708 software suite on your PC and within your free update period for your serial # , download the latest system update and vehicle software to your PC then copy and paste to the new SD card in the card reader