Who would sell that?

There are already at least two Facebook groups concerning Ariels.

The rear gurard might not be hinged, but screwed together with 2 1/4" bolts.

The cover over the gearbox and the cover in the middle of the clutch dome indicate it as a 1932 model.

You don't need it. If your 28 is like mine, you have 2 breathers from the engine. One of them blows air with oil in it onto the rear chain. The other on the primary chain. In 10 years I have hardly had to adjust the chain.

There is such a seat on my 31 MF.

The elastics can be found on truck covers. They are used to keep the lower part of the cover to the bottom.

Hi Klaus.
What is the content of the can in the middle?

Yesterday I went on a 50 km trip on my 1928 model A. Somewhere on the way it lost the intake trumpet, so now I'm looking for a spare. The carburator is a Brown and Barlow, with which the bike was delivered from new. I found an Amal one in one of my boxes. That could be pressed into service, but I do...

I can second Paul on this. I also tried to put Mini orings on the valves.They were burned to pieces in very few km. Luckily the pieces didn't fall into the lower engine. I could pick all of it out.