Its not a locker in the traditional since but almost every locker available today "locks" in a different way. The ECTED locks by running a electric current through an electromagnet that then forces the clutche dics in the LSD part of it together forcing it to "lock" up. The ECTED is advertised as a locker AND a LSD not just a LSD. And however some may debate over whether or not it is a "locker",
that is what it does and yes it could at some point be overcome and slip, but reviews say that this does not seem to happen and it works perfectly. Maybe its not a rock buggy ready style locker but for the average wheeler it seems to be just the thing for those that want a LSD and a locker.
I went to thefind.com and and typed in Detroit electrac and it came up with many different places to purchase the locker from however who knows if its just pages that these web-sites have yet to fully delete but here is one from Currie
http://www.currieenterprises.com/cestore/productsRE.aspx?id=2113
they are a big business for the drivetrain world and I would expect them to keep their site pretty up to date so check them out give them a call and see if they still have one.