You can also check by looking at the original
boler specs. If memory serves me right a boler is 6' 11" high on the outside, with a head clearance inside of 6' 1". That leaves about 10", allow for the materials of the roof and floor, the bottom of the kitchen floor should be about 9" off the ground when the trailer is level.
Then again, somebody may have previously swapped the axle thinking the "chopped" or lowered look, was desirable.
Noticing that you are in Halifax, I presume there are a lot of marina's around. Maybe you could ask one of them about the
fiberglass repairs to get an idea.