Correct, nothing about the starter said that it was a marine starter. And before everyone starts a flame war about why I shouldn't have a non-marine starter on my boat, let me present a few pictures of the original starter. From what I can tell, only sealant was added to the solenoid / electrical contact area to keep fumes from permeating into the case and possibly causing an explosion. As for the new starter, I fully disassembled it to inspect for seals, gaskets, and other forms of spark / explosion prevention. Besides two moisture drains, the new starter is completely sealed. Probably even better because it doesn't have any gap around the bendix area.
To address why I didn't run the block drains straight out, I haven't made up my mind yet as to whether I want to keep them as right angles or not. It would be easy enough to remove the right angle brass fittings to poke through any rust blockage should the need arise.
