'29 to '31 starter motor type?

[Tony Press]

Hello all, I'm after a correct starter motor of the late vintage type between the bacon slicer type and the side crankcase mounted type. I understand that this type isn't interchangeable with the other types, but I'm not sure which starter model type I should be looking for? It'd also be useful to know if there's an easy visual identification for this sort?

On a semi related note I'm also after a floor mounted starter button. In the absence of an original, are there any 'modern' types that are known to fit? I wondered if the early mini ones would be about right but I think they're too small.

Any input much appreciated!
Rupert

I understand the 'vacuum cleaner' mounting is very hard to find.