I may as well chime in on this lol. My two Model 2's are as follows:
#17,000 - 290mm, circlip axles (transitional?!)
#54,000 - 280mm, circlip axles
Re the topic of rivets or bolts on the badge, my 17,000 with a Model 1 badge came with one side alloy riveted and the other with a brass dome nut. Still not 100% sure which is correct, but I'm leaning towards the rivet based on this image from the March 1957 ad:
![[Linked Image from i.imgur.com]](http://i.imgur.com/wYMNGcr.jpg)