These are indeed terrestrials and the various species are found all over Europe from up north in the Russia, and all the way down to the Mediterranean.

I'm not too sure about availability of these plants in the USA, but they are available in Europe... it looks like some species are being flasked commercially...

I suppose you have a couple of issues to deal with, ie local availability, and if none, whether CITES and the costs of importing the goods are within reason...

good luck with the search!