Hmmm, This dosn't sound good. I think we need to see some pics ! The parts are, the intake ( the piece that bolts to the bottom of the hull ) The suction housing ( forward part of the pump that curves from the intake to the bowl) , the bowl, the transome adapter (trim ring that goes around the bowl and mounts to the transome (back of the boat) ), then the steering nozzel. Thats the basic version

. If you are sure you have a Berk intake than I dont think a Jacuzzi loader grate will work. Also you should look up inside the intake, if I remember right the WJ is smaller and shaped different than a Berk and there might be some ugly misalignment issues in there (bad for water flow).
IMO, If its a berk intake, get a berk jet.
Dont worry, the real experts should be here in the am to help figure this out

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