Last November
fishmom forced me to pre-order Habenaria radiata and H. radiata 'Ginga' from
Kusamono Gardens (which currently has them in stock, along with other terrestrial orchid tubers.)
They arrived today. I'm putting them into the refrigerator for a few days until I get things together. I'm planning on using small grain pumice and peat moss mixed together 80%:20% and following instructions on the Kusamono Gardens Web site. I will keep them in my sunroom during the summer, where the evaporative cooler keeps things to 80 F / 27C and 70% relative humidity. I don't think they'd survive our summer otherwise.
One photo shows the two 2.5" / 6.25cm across condiment cups holding the tubers in moist sphagnum moss. The other photo shows one tuber, exposed.