I have seen a product for that purpose, so you might investigate that. I considered installing that on my last boat's 892s, but was persuaded it is more trouble than it is worth. I also considered having it installed when my current boat was commissioned, but was again persuaded that it isn't worth the cost or complexity, particularly for two reasons: 1) the engines are QSM 11's, which are electronically controlled and turn over 4 revolutions before ignition -- supposedly that is enough to produce oil flow/pressure before the loads of a running engine can do any damage to bearings, and 2) the way I use my boat, once the engines are started, I keep them running at least for hours, often for days, so the startup is relatively inconsequential.
The theory that prelube extends engine life is predicated on the assumption that a lot of bearing wear occurs at startup. I don't know the empirical evidence for that but do note that some high-end cars with expensive engines shut down the engine when idled (at a red light for example) more than a few seconds, and start right up when the accelerator is pressed. If the startup was causing lots of wear, I would think that those cars, especially if used primarily for city driving, would have drastically shortened engine life expectancy.