What cars (and models) would King George V have used for official visits in the 20s? And which mascot would be on the bonnet?

Big upright Daimlers of various types, usually Limousines or Landaulettes coachbuilt by Hooper - George ordered 8 between 1909-24. http://www.imcdb.org/vehicle.php?id=1153433 , http://www.imcdb.org/vehicle.php?id=395318 , https://www.conceptcarz.com/z20418/daimler-57hp.aspx , http://www.remarkablecars.com/heads-of-state-cars.html , http://www.ehattons.com/36104/Oxford_Diecast_Ltd_43RD001_1929_Royal_Daimler_King- _George_V_Sandringham_/StockDetail.aspx and http://www.ehattons.com/42573/Oxford_Diecast_Ltd_43RD002_1928_Royal_Daimler_Quee- n_Mary_/StockDetail.aspx .

Mascots varied - the royals often put their own on whichever car they were travelling in, and sometimes switched them around. So KG often had Britannia on a globe, Queen Mary Britannia holding a crown. (Elizabeth today uses personal mascots of St. George slaying the dragon or a single standing lion on her Bentley)

Interesting choice. Duesenberg model J is the first thing that came to my mind.