If it helps make the FDDI implementation project a success, I have found the versions you need below
http://software.unl.edu/pub/mac/supported/System%20Software/Net%20installers/Apple%20SW%20%28N-Z%29/Network%20Software%20Installer/
http://software.unl.edu/pub/mac/supported/System%20Software/Net%20installers/Apple%20SW%20%28N-Z%29/Network%20Software%20Installer/