Your best bet is to go to taxidermy.net/forums post in the taxidermy industry forum and ask for MO freeze dryers in your area, someone will show you the way. and how to pack and ship.
Now I personally don't believe in freeze drying since the epa suspended the use of edolam-U there are no real good preservatives and some think is not needed ,but that is not my personal experience when I bought a bunch of rattlers for resale and several months later they rattled inside and were filled with african beetles.