Maillard large diameter freewheel remover

If the cup has detached from the hub body and is not sitting tight *then it's pretty serious*.
I think the cups should be a press-fit, but you could try epoxy to stick it in. Alignment will be tricky.
'Mend a bike' in fulham has the tool to get that freewheel off if you're going that route.

Yes that's what I thought...
Not sure I want to go thru too much trouble with these...

Thanks for that, ant the shop address!

Loic