OK for you guys that have a D44 electrac and manage to bust up your electric actuator like I did there is some information for you. The actuator is manufactured by a company named AAM (American Axle Manufacturing) and their part number is 46003022. This is the same actuator used in the 2002 - 2006 Chevy Trailblazer 4WD for the front axle disconnect (Chevy part number 12471631). The prices range from $85 to almost $130 depending on what dealer you get it from.
BTW: The customer support at Eaton is WAY better than tractech ever was. They were VERY helpful this AM and confirmed the Chevy part number for me. I asked whether they were going to keep selling the Electrac and he said the future of this locker was "undetermined" but that they were still selling it and selling parts for it.
Eaton & Detroit Locker Differentials, email@example.com
I suspect as soon as their inventory is used up they will discontinue this product but who knows.