If you click on the photo, you should see the full sized version.
I checked 4 vendors rather thoroughly (that I know are reputable), and others I just visited when I got a google hit. I wanted to check Gold Country Orchids too, but their website is empty. Feel free to check any other good vendors you know of!
Species names in red may not be good choices due to temp requirements, or was recently already a project plant. Rows highlighted in green are plants that are easily available, and in orange they could be good, if the vendors have more than 1-2 in stock!
Everything else is difficult to find, or only at one vendor (and they could have 1 plant or 30 plants!)
I also added 2 new plants to the list, Den aberrans and Den unicum. They popped up many times at vendors when searching for others on the list, so I thought they could be nice candidates!
I did not pay much attention to plant size, which I should have done. Once we've narrowed down the list we can go check this for the remaining plants.