Thanks everyone, I'm getting confused about gearing now!
I will be using a gear cover (when it arrives) and am looking to run a 19T motor, would prefer not to hack the car about though as it's pretty tidy.
I've also spoken to RW and he's said that they can easily make either a suitable spur or a spacer for a spur intended for another car.
The guy was very helpful and thought it was 4mm and that they'd made them years ago with teeth in the 70's range. So there's a chance they are almost 'off the shelf' assuming that I can get the gearing sorted!
Dave (Belsten) does have a spur on his Mid, which would be great for measurements but it's 64dp in that weird material that tended to turn to powder when it stripped!
Thanks again everyone for your help
