Dart SHP 180cc Straight Plug Aluminum Heads,GM Hi-Performance 4 Bolt Block(new), Hydraulic Roller Camshaft,edelbrock performer(air gap),nodular or better internal balanced 3,75 stroke cam,hyper or forged pistons,keep compression around 9-9 1/4 for a boat, the engine like this would cost me about $7,500,not cheap and likely 430-440 hp at 5,200 RPM.
power can be adjusted up or down as required,your choice.Im thinking an engine that will last years and be reliable.
are you planning to use fuel injection or carb? for skiing F.I. would be nicer. what kind of exhaust manifolds are you using? wet or dry?
an engine like this would make around 300 hp as low as 3,000 rpm with peak torque around there depending on camshaft chosen.
When I built my 434 I purchased my parts from eastern states and had them air freighted to Vancouver Canada,it was cheaper to ship than the hood I bought in California and had sent by truck.Look into freight costs and see if you can get a package sent?