I see you are in NZ. Yes, agreed, Model D. I know there's a 28 Model E there that was with Peter Wright, I think an AOMCC member.
You show up as a member, so here's a link to the 1928 factory brochure. User name and password are inside the cover of the Cheval magazine. The artwork and detail is excellent. We're lucky to have these. http://www.arielownersmcc.co.uk/members ... /index.htm
It looks like the same bike to me. Even a bracket to stop the panniers from fouling the wheel.
The electric lights would have been an extra.
'51,'56 Squares, '48 VH, '27 Model C, R67/2, Mk IV Le Mans, '06 Super Duke and Ariel projects.