Charlize, my thoughts

From yeo itself - hope he does not mind for copy/paste here:)

"hello!
wow! how any years have you kept her? :)
charlize input impedance is 50 kohm. so practically any tube preamp with output impedance less than 1 kohm should be able to drive her sufficiently.
whichever tube preamp topology you select, it's always best to have the volume control before the tube stage.
volume control after cathode follower is a bad idea.
thx!
yeo"

"
hi!
i'm sorry. i confused myself.
we recommend a 50kohm volume pot as charlize input impedanc is 10kohm. sorry, not 50 kohm.
been so long... i forgot all this details.
yeo"

Just for future reference - who knows what future will bring us....

All the best, guys!