The Williams FPTK for grooved receivers will fit the 9422. You'll need a higher front sight IIRC. A number of people around here use that rifle/sight combination for cowboy without complaint.
Also, the triggers on the 9422 are pretty heavy as they come out of the box. (The trigger return spring must have been dreamed up by a lawyer who previously designed leaf springs for John Deere!) If you take it to someone who understands how much to bend that spring, the pull can be very easily reduced to a much more useful weight. Often, it isn't even necessary to stone the sear or hammer once the spring tension is 'fixed'.