When I get to the shop tomorrow I will remove and clean the housing & O-ring then eyeball the assembly to assess the feasibility of incorporating a gasket.
My confidence in the o-ring alone is not real high.
I’ll report on the results.

Didn’t enter the water today; the conditions were a bit wild for my liking. At 72 years of age I figure it’s ok for me to pick my days. Getting “worked” in 35 degree water is all that funny anymore.