From the "History of the RCCS" 1st div signals and HQ lost most of their vehicles when three transports were sunk. All their surviving equipment was hand carried ashore. From the book "It was more than two weeks before 1st Div. Signals vehicle compliment was made up, the replacements being North African veterans, many of whom were scarely road worthy".
It also states they made good use of mules. Don't know whether they were sand or OD.