Moving and Re-Planting a Tree Fern?

I'm no expert on them, I bought my first ever Tree Ferns last May. I had a little accident with one so you can see the root growth it made (it is probably the same size as the one you mention):
http://gardenerscorner.co.uk/forum/tropical-gardening/39436-tree-fern-root-growth.html

I would say do the usual thing like when moving and re-planting an established tree/shrub i.e. try and get as much rootball as possible.