On this day, in 1908, was born....

On this day, in 1908, was born Sir Anthony Richard Wagner, a former Garter Principal King of Arms.

I couldn't find his personal arms anywhere - perhaps your heraldic libraries have it somewhere?

Meanwhile, the arms of office of Garter are:

Arms: Argent, a cross gules ; on a chief azure a crown enclosed in a Garter between a lion passant guardant and a fleur de lis, all or.
Coronet: the coronet of a King of Arms

Additaments: a) two batons royally crowned Or in saltire
The dexter one is showing Argent, a cross Gules within the Garter proper
The sinister one is showing per pale England and the Royal Arms
b) The collar of S of heralds (?)

https://commons.wikimedia.org/wiki/File:Coat_of_Arms_of_the_Garter_King_of_Arms.svg#/media/File:Coat_of_Arms_of_the_Garter_King_of_Arms.svg

File:Coat of Arms of the Garter King of Arms.svg - Wikimedia Commons