Hi all,
I appreciate all the comments and thoughts, thank you.
I'm just going to sum up what happened even though its a bit of a mess.
Basically, the requirements that were given around privacy and for it being a non-physical approach evaporated. The recipient of the data eventually came back and said the network in that part of the world is incapable of receiving large files, so please mail physical. So thats whats going to be done, a crypted external hard-drive. I am grateful that this is the solution was deemed acceptable because in this particular case it seemed the best.
The approach that we were preparing to do was to crypt and chunk using 7-zip which looks like a great product for exactly this types of problem. We were then going to make it available via sftp to the recipient. The reason for setting it up that way was so the recipient could take advantage of the faster download speeds (as compared to upload).
Thanks again,
Micah