I have a South Yuba mining Highbanker that came with the dredge attachment for the hopper. I have not used it as a dredge but love it as a highbanker. Good quality stuff... probably the last highbanker I ever have to buy.
They are made in Nevada County and he does a good job with them. Nice quality stuff. The miners miss that comes with them is the better, thicker stuff that doesn't squish down under your riffles.