OMC Cobra leak from Carrier bearing O-Ring

[subcrx]

My 87 cobra is the 5.7 model. Its gotta leak from the rear of the carrier bearing o-rings. I replaced them once already. Held for only a few months and now its leaking again from the same spot. I remember when changing it out the inner walls of the lower unit housing were pitted a bit and could cause it to leak again. I was thinking coating the walls with a type of epoxy and sanding it down smooth and flush. Anyone know of the right epoxy or fix for this?