Who makes a good sight replacement for the factory rear sight on a CZ 550 in .458 lott. In other words what fits the dovetail already present?

I had to replace one recently. The ones from NECG which come from Recknagle are long enough but not wide enough to fill the base. I ordered a replacement from CZ-USA ($68) and am hand filing & polishing it so it doesn't look so rough.