I think the original deCarbons can be restored.
(At least the ones in the Flaminia could be restored)
To be honest I have never heard that Fulvia deCarbons could be/ were ever restored ??
My local shock absorber workshop was a bit sceptical when I asked them to restore the Flaminia ones.
They were a bit afraid of availability of mainly gaskets, turned out they could use Koni gaskets.