What elevation in regards to sea level are you? Is your carburetor the correct marine 2 barrel Holley version? Are you sure that your boat does not have water or mud trapped inside? I once had a customer who bought a boat that must have sunk at one time and it had mud trapped in the double bottom.
I had a customer with a 24’ Formula/188/ 1.50. I cannot remember either a 15“ or a 17” propeller. A heavy deep “V” boat. He fished out of the Mississippi river into the Gulf and never had a problem getting on plane and hitting 4400 rpm.
If you still have the original cam it could be copied. There are places that do that.
I am at about 950m of elevation it is the 2300 Holley carb although not specificly marine.
I had the whole floor out and there was a little water but i cleaned it all out and dried it so should be all good.
On the first original cam i somehow groud the dist gear so I bought a used cam from NLA marine parts from a mercruiser 888. But then when I had truble getting on plane and to rpms a guy told me that maybe my cam was run down, not enough lobe lift, so i bought a new set of lifters and a cam from COMP CAMS. I still have that used cam where there is nothing wrong as far as I can tell, it ran the same with it as with the new.
