Folks...

I need some help, advice and direction:

Out in the boat the other day and suddenly lost power and motor died
('99 Yamaha DX150). Starter wouldn't turn the engine/crankshaft. I
backed up the shaft manually by turning the flywheel(?) on the top of
the motor and then the starter cranked the engine. Lots of rattling
inside. It sounded REALLY bad, so I didn't run it anymore and got
towed in.

Mechanic from the local shop came by and after pulling the plugs,
spraying Deep Creep in the cylinders and turning the shaft back and
forth manually finally cranked it a few times with the plugs still
out. From the noises, he determined that I probably had a bent (or
"egg-shelled"(?)) rod or that the rod was broken. He looked at the
plugs and saw rust (slight) on one and a little salt water on the
bottom two plugs. He figures the engine aspirated some water (I've got
a hole in the bottom of the cowling) and one of the pistons seized in
the cylinder and thus bent the rod.

So, according to him the powerhead needs replacing or rebuilding. He
says it probably makes more sense to buy a rebuild with the warranty
(1 yr). He shopped around and called me with a total price of $5,700
to $6,100, including PH, shipping, installation, and various other
incidentals. The PH itself was $3,900.

Now for my questions:

1. From what I've said here, does it sound like a correct/reasonable
diagnosis?
2. If so, is a rebuild, rebuilt or new PH the only way to fix this?
3. Does the price/amounts I mentioned seem in line or expensive?
4. Should I just shop around and try and find the best price on a
quality rebuilt PH myself and then let the shop do the install?
5. Where are some good places to get good prices on quality rebuilt
PHs?
6. I've found Blackbird Industries online. Does anyone know anything
of them: Are they reputable and is their product good?
7. Where else might I try?

This is a lot, I know. And I appreciate you taking the time to answer.
I just HATE being ignorant enough about something that I don't know
whether I'm getting the straight scoop or not. In this situation,
though, I'm at the mercy of the folks I ask.

I'm coming here for objective, knowledgeable information and advice
that can help me decide what avenues to investigate/pursue...

So thanks gobs in advance...

Charlie