My guess would be 3.5 to 4kgs, nice fish.
That is about my PB as well, but that is from offshore. From the Bay my best so far is 58cm, not sure what it weighed probably around 2kgs I guess. Of all places I got it off our pontoon in our backyard on a sp (a 100mm sqiggyfish in pumkinseed or similar, if I remember correctly). I must see if I have a photo somewhere?
Have not put a lot of time into chasing them yet, but aiming to start this winter.
Cheers
Dave