Having thought about this for a bit, it's more of a grind than a crunch - a bit like you are trying to put it into gear without using the clutch. It's only occasional though so I am thinking it may be release bearing or slave cylinder. The judder is defo clutch plate so that will need replacing. If I buy the kit with a new bearing & it still grinds then I will think about the slave or possibly master.
As far as clutch kits go, I have no idea what size flywheel is on the L20 or L24 so I bow to judgment that it could be 225mm.
If this is the same as a Laurel then these seem to be widely available.
Will have to start saving the pennies!!
Cheers
Paul