Arthur, the second photo (4 segments with holes for the Cush rubbers) matches my late Mk2 (1979) wheel I have just taken out.
Mine is silver rather than black finish.
Agree second is late MK2 in black the other ofvthe first three can be used with slight modification I guess why kept.
The last one is very interesting as I do think it's Silk as I have sprocket for that style and think it was used on a late MK1 with alloy conversion.
This is the thing with sprockets as well as there are different front types depending on if bolted or cast and same with the rear sprockets as some had 4 hole some 6 etc etc