Sorry Carnut, all mostly true, but the first examples did go by another name (that you've not listed) and I have the evidence next to my laptop! So, still locked to you...
Noted, but that info may not be right!
I actually spoke to Den Tanner who was the owner of Pilgrim and designed the cars.
It was he who told me 100 cars were made in addition to the prototype, the Mk Is and IIs I listed earlier.
He said that your information can't be right as no other name was used!
He was insistent that all cars made, including the prototype, were named the Hawthorn.
You can ring him yourself to check if you like, I can PM you his phone number!