Isn't that an aft cabin model?

Assume that you mean you have access through the rear bulkhead of the engine
compartment to reach the port packing gland. The companionway steps from the
salon to the aft stateroom terminate in front of a hanging locker, correct?

Some SWAGS:
Could it be that the access to your packing gland on the starboard side is
vertical, rather than horizontal? Look for a removable panel in the base of the
starboard hanging locker in the aft stateroom. That's just aft of the bulkhead,
and should be in the general area where one would expect to find a stuffing
box.

Another possibility-
Is there carpeting in the aft stateroom? Is it original, or has it been
replaced? Somebody might have slapped replacement carpet down over an access
hatch at the bottom of the stairs.

Last but not least, those steps are probably not molded as part of a fixed
cube, but laid up just as a series of treads and risers. It's possible that the
stuffing box can be horizontally serviced with the steps in place, if there's a
removable panel. Any screws visible on the backside of the steps?