Just eyeballing that rig, I'd say, 800 for the hull, empty (and assuming it doesn't have water-logged wood or foam...), 250 for the motor and another 300 for the trailer. Add 200 pounds for gas and gear and all-up you are probably in the 1350-1500 range.
You can probably get more accurate that this, especially if you take it to a weigh scale station.