When MG did this for the BGT Jubilee dash plaques (which were optional) the badge was completed with a space for the number, which was added by the dealer.
In this case the Morgan factory could easily do this - is the production number the chassis number, and did they start at #1?
MG originally started chassis numbers with 101, then later 0251, with prototypes starting from the same point and working backwards.
The MG factory phone number at the time was Abingdon 251.
