GB wrote:

If I knew what to look for I might find somewhere that sells them,
but you guys probably know already.


http://www.bakfin.com/terminology.html

Okay, thanks, I'll look for star washer. Screwfix?

Star washers are the wrong thing to look for. Star washers are used to
prevent nuts undoing themselves when subject to vibration (except they
don't work very well at that). What you need, if I understand you
correctly, are Shaft Rings which are applied to shafts to stop the
wheels falling off.

http://www.rotorclip.com/cat_pdfs/tx.pdf