Blue Moon has two service batteries in the compartment under the port bunk, as in Dirk's photo. She has a starter battery under the aft end of the starboard bunk, which annoyingly cuts up the space in the compartment so I can only stow small things round it. The cables from the starter battery run through those conduits to the port compartment, then under the service batteries to the selector switch.
I would be very surprised if you could get even the smallest inflatable dinghy into the front starboard storage space, although you shouldn't have to go through the little door as the top is open under the bunk cushion. Life rafts are much smaller - or at least nice new ones are, mine is huge, weighs a ton and hangs off the pushpit causing the boat to list to port but that's another story.
Incidentally, my service batttery compartment has a tight fitting lid with screws to hold it in place. I gather this is good practice: were you unlucky enough to be knocked down you would not want to compound your misfortune by having the batteries fly out and destroy your saloon.
Peter Dann
Blue Moon 325/32