Someone correct me if I'm wrong, but . . . I believe that when they are talking about the elevation of plants in their natural habitat it is referenced because of average temperatures, light intesity, and humidity at those natural conditions. I don't believe that it has anything to do with atmospheric pressure.
With that in mind, we adjust the climates of our homes to be comfortable. These conditions that we like will be liked by many orchids. There may be additional things we can do to help our orchids like adding supplimental lighting, humidity trays, misting, potting materials suitable for our environments.
Now all that is left is to figure out what you can offer in your home and go and buy some orchids.
