'77 Ski Tique 302 Cracked

Here's the boat I failed to properly winterized after 5 short years of owning her. Went out for a shakedown and after a few minutes checked bilge where I saw a milkshake running down between trans and the block. Shut down and checked dipstick where there was also a milkshake. So I have water in the oil due to a crack in the block. I haven't located the crack(s) or separated the engine and trans, but am certain I will need a new block or a new complete. My question is how do I source an engine or a block for rebuild and also is it worth doing the repair or selling her as is to a guy who can do the work. The boat is near perfect, 900 hours on the motor, new period correct interior, taken very good care of (until I destroyed her) and was pulling barefooters last summer. She really is a beauty. Any suggestions from the correct craft know how would be greatly appreciated. I have nowhere to work on the boat and it is stored at a marina. What might a guy pay to have the work done? I can pull the engine myself where it is stored in Lake County Illinois. Thanks a bunch in advance.

Zach,
Did someone or yourself do some checking to determine the problem is a cracked block? If so, fill us in on how the determination was made. What didn't you do with winterizing to make you think it cracked the block? I ask since there are other problems that can cause water in the oil.

Orlando76 wrote: Hadn't fully grasped the difference between marine and auto short block

Brass core plugs. Get the short block and install the brass core plugs!!!

Thank you all for the replies. PBrainard, I don't remember putting coolant in when I stored it. I drained the block and exhaust logs and left the plugs out but don't recall adding any coolant. I need to pull the motor and get a good look, but I don't think it's a head gasket. It runs great and there's no steam or blue smoke in the exhaust. What are your thoughts? Thanks.

Thanks for the reply. Haven't checked the freeze plugs but will get to the boat this weekend and will post my findings. Thanks for the optimism! I will expand my diagnosis.