Leaks

I have at least one leak in my 86 supra comp and its got me weary of running it with any ballast. It looks like its leaking around the drivshaft fitting through the hull and/or the rudder. Its not bad but a couple gallons an hour maybe more which sucks. I think i'm gonna take it to the dealer tomarrow because i'm not sure i trust myself to fix it.

I put some silicone caulk around the areas but it basically got blasted off by the water.

Anybody else deal with this on an older boat. Are there seals that have gone bad?