Companion plants for Polyrrhiza lindeni in terrarium

[Cewal]

I've had orchids for about 8 years but this is my first attempt at a small terrarium. The only plants I have in it are two Polyrrhiza lindeni orchids. They are doing fine in it (artificial light, very high humidity, and no air circulation), but I don't know what else to put with them. I would appreciate any help with recommended plants and where to buy them. Thanks.

[Ray]

Jewels?