The 311 is an SD, MPEG-2 only receiver. It will not work on the Eastern Arc. I'm not sure they will activate it for use on the Western Arc.
Discontinued long ago.
You might be ahead to go with a Wally.
I am not familiar with the King Dome LNB, but I believe they are mostly used with DirecTV. Even if you got a new style LNB, it might not work with a King Dome.
There are some self aiming antennas available.