Mercruiser block replacement

So for anyone who read my last post. Block cracked and is toast in my 2004 sv211. 330 pcm excal. My mechanic said he can swap it out with this block and get everything done for around 5500 for everything. Any advise on why it wont work or is it my best option. 343 bobtail is 10k just for the motor. Here's the link for the block. Thanks in advanced. https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F311913774478

I just put one of these in a few weeks ago. Had the thing in two days. I'm very pleased thus far but have yet to get it tuned correctly. Service is top notch. Poeple answer the phone and return emails straight away. Can custom order anything you want pretty easy. Good prices.
http://centerstateengine.com/new-marine-engines/new-base-marine-engines/5.7l-marine-base-engines/

Don’t forget to factor in the cost of swapping all your parts over to the new long block... it’s cost effective if you’re doing the work yourself but much less so if paying shop labor rates. There is also some potential concern if the new long block has different bore/pistons/compression ratio from the original... I am not sure how flexible the tune is on the excal. Some have reported issue when rebuilding the GT40. Both run closed loop (no o2 feedback).

If you were to go bobtail, don’t forget that your original engine has some value and could be resold... one more thing to factor in.

Good advice. I talked to a professional boat mechanic and they quoted me at 6k. That's for the new block, swapping everything, install and a 3 year warranty. I think I'm going to go with that. I'm not mechanically inclined enough to do all the swapping and if there was a part that was faulty I wouldn't know what to do. Plus having a warranty for the next 3 years would be great