rough figures
If it is older it may be 2500 lbs, newer 2300 lbs, and add the trailer of variable weight to 1000 lbs also. Then add the contents and liquids on the boat eg motor and water. The think about he placement of it relative to the axle and the trailer tongue. Your hitch should be able to tow 3500 with 225-350 lbs tongue weight. If it is too little the trailer may whip, too much and it affect steering the truck quite a bit. Some things to consider, anyways.