This is from Moyer's web site:
Complete exchange engine options:
$5375 (late model direct drive)
$5430 (2:1 reduction)
These prices do not include a $700 core charge which is refunded when we receive your rebuildable engine in our shipping container.
I have nothing but positive things to say about my A4s, (I had one in my Catalina 27 and now one in my Morgan 33). I found that using Marvel Mystery Oil not only kept the cylinders clean, it is also a top cylinder lubricant that helps seat the valves and seems to minimize combustion chamber wear. I wouldn't leave the dock without it.
A couple weeks ago, I noticed my oil pressure was down to just 25 PSI, which is a big drop from where it usually sits at 40 PSI. I was beginning to worry, then checked my log book and found that I was about 50 hours plus overdue for an oil change. After changing the oil, I went on a short trip and the pressure was right back up to 40 PSI.
Also had some starter issues, which turned out to be low battery voltage - I guess 7 years is a lot to expect from my Trojan T-105s, especially considering how much they are abused by the owner. I can buy these locally for $129 each. The biggest problem for this old codger is lifting them into the boat, down into the cabin and placing them into the battery compartment. Guess I'll have to round up one of the youngsters in the marina - they're a lot stronger than me.
Next season, I'll change the water pump impeller, which is now on it's 6th year.
Those Obendorfer pumps and impellers wear like iron.