For less money than tek wants for that Chinsy feedhorn you could get a genuine Chaparral ortho from Vincor dot com.
Those Chinese scalars & feedhorns just aren't that well made.
Who knows where they get the aluminum alloy for casting either - could be a low grade alloy that corrodes to white powder in the first rains. Ever seen the rampant corrosion inside an old Toyota intake manifold? Like that.....