The only symbol of Charlemagne of which I am aware is the Iron Crown which represented his role as the first Holy Roman Emperor. The crown has beeswax and other datable items to hold its jewels in place which date it to the Emperor's time. There is some argument that Charlemagne himself adopted the Roman Eagle as his own personal symbol, as it was the symbol of the Holy Roman Emperor. He has at other times been depicted kneeling before Pope Leo III when he was crowned Emperor of the Romans on Christmas Day, 800 C.E. Since his Empire encompassed both present day France and Germany, there are images of him showing the French fleur de lis and German Black Eagle as his symbol, although both were created after his death. If your need is for a simple bust of Charlemagne, you might look online as there are any number of busts, statues, etc. of him available.