No doubt there are many others, but here are two links to scribd.com for material related to Testamentum Domini.
First is a brief article on the dating of the apocalyptic section with which the piece begins. Whereas this does not date the church order itself it does at least provide a terminus a quo for the final level of redaction.
Second is a pdf of the Cooper-McLean version.
http://www.scribd.com/doc/125622575/Apocalyptic-Section-of-Testamentum-Domini
http://www.scribd.com/doc/58917079/Testament-Savior
ancientchurchorders 