Terrestrial orchids are very nearly the only thing I've wanted in my
gardens that I've been reluctant to add, because zone 8 is just barely NOT
cold enough for their seasonal chill without having them in pots that can
be popped in a refrigerator. So all I've planned is to add additional

Hmmm, And I thought zone 8 was almost tropical. ;-) But then, I am a
Canadian for whom -10 degrees Celcius (that would be about 14 degrees
Fahrenheit for 'merkins) and snowing is a mild spring day! ;-)

But seriously, Red's Hardy Orchids is in Oregon and Frazer Thimble Farms is
in BC. Unless my sense of the geography of your part of the world is
terribly distorted, you should be close enough to both to make a day trip or
a weekend trip to visit either, and pick their brains about what ought to do
well for you (assuming both have facilities open to the public, or at a
minimum can be visited by appointment). I have driven from Northern
Saskatchewan down to Colorado in less than a day, and I'd bet that is a much
longer distance than from Puget Sound to Oregon or from there to BC.

And I saw quite a number of species on both web sites that are of no
interest to me because they're "hardy" only to zones 7-9. But, really, does
the word "hardy" really apply to such tropical climes? ;-)

Cheers,

Ted