I have had very good luck having Bill Maxwell make them for me. I also had a katseye in a Xti that worked well
Call Bill at 404 244 0095, tell him you will order a Canon screen from B&H and have it shipped to him
Then discuss the max aperture of most of your lenses which will determine which coating he puts on the screen.
I also have him put a rule of thirds grid on it. He has probably made half a dozen screens for me. Some times it takes a month or so to get it.
Marc