As you know, the Whitei itself does not spore, so division is the best/only option. Most of my plants are 'full Whitei', but I have a few that have both the sterile Whitei fronds, and also some fertile Rigidula fronds.
As stated earlier, I thought of growing some of these from spore, to see if the Rigidula spore( quite common) can produce Whitei ferns (rare plant). Perhaps the result could be just common Rigidula ferns.....or they could produce Whitei ferns....or possibly plants with BOTH sets of fronds.
I just don't know.
If you would like some fronds with spore, ie Rigidula fronds, I will gladly post some down to you. At this time of the year, the fronds will die-off awaiting new Spring growth. If the spore you need is obtained from the almost-dead fronds, let me know before too long as they're dropping fast. If you need new fronds, give it a couple of months.
Sorry about the photo.....reduces down to 250x250 and produces low-res when zoomed-in.