Sometimes people use the words pump and motor synonymously so I just want to make sure I understand completely. Are you proposing to swap JUST the motors or the entire pump with motor? As Ben pointed out, downsizing just the motor is a problem but if you swap the entire pump, that is ok.

Without any additional information, my guess is that pump is producing at least 65 GPM which is technically more than the filter can handle. A 1 HP Jacuzzi would be slightly better but still exceeding the 43 GPM spec. To get down to that flow rate, you will probably need the smallest AG pump on the market. Either a 3/4 HP Optiflo or Dynamo pump.

Can you post a picture of your current pump (entire pump, not a close up) just to make sure? Also, can you tell me the service factor off the pump label for each pump?