Help identifying AC Adapter needed?

[LiQiCE]

I lost the AC Adapter to a Directv HR44-700 and I'm trying to find a replacement. Directv won't sell me a replacement and I tried some popular DTV Resellers such as SolidSignal and WeaKnees and they don't sell it either. Hoping that maybe I can find a generic replacement. The AC Adapter is a +12v 4A power brick, but the connector on the end is not standard.

Here are images of the power brick and the receiver itself:

Thanks for your help!