David, thanks again for the tip about the additional pictures. However, I now have some questions.
The first picture below shows a spindle with tapered wheel bearings. Between the bearings is a sleeve and an additional part that appears to be adjustable in length, with a knurled outer diameter and a grub screw to block the thread. Does anyone recognise this design?
Is it an adjustable 'crush sleeve' for adjusting the wheel bearing clearance?
Can it be bought off the shelf?
What would you call this? (This will help me find it online.)
On the far left, there is another unfamiliar part. Usually, there is a big nut to tighten the wheel assembly; in this picture, however, there is a 'cross bolt' to prevent the nut from spinning? What else could it be?
The second picture shows two spindles, but the quality is not so good — I can't see any clues.
I look forward to your replies. Thanks in advance.

