You would think that a variety so readily available in Europe, would be offered by some US nurseries. I haven't seen it listed anywhere lately.
Might try Judith Jones at: judith@fancyfronds.com and Sue Olsen at: foliageg@juno.com (Foliage Gardens) for a possible source. Sue is also founder of the Hardy Fern Foundation, hff@hardyferns.org, which may be helpful in locating a source. The American Fern Society, amerfernsoc.org, has a forum where you can post questions (registration required).I'm sure some member(s) would know of a US source.
Good luck!
Rb

Thanks Rb, good information.
mshostas

Hi, I'm propagating Polystichum Setiferum (Plumosum densum) from bulbils (i.e. live plantlets that develop on the stems) with little difficulty. The reason is simply that we are in the process of moving house and are determined to take this lovelist of ferns with us, the original 20-year plant being too established to move now. I'll happily send you one, but I'm not sure if they can be legally imported at your end? What about some spores which you can develop in self-seal bags? Incidentally, it doesn't seem to be too easy to buy here either. Plenty of other Polystichums about, but not this one. The ref page doesn't say it's of a Plum.dens. but it is.

Here is a link that might be useful: Useful reference page