I dive the area just north of Sunrise aka Oakland Ridges both south and north of the buoys, and yes, staghorn can be found from a beach dive.
The first reef ledge is within 50-100 yds or so of the buoys near the beach.
Smaller patches of growth exist and are not too hard to find.
If you go offshore of the biggest pair of condos right where A-1-A turns inland from the beach (public parallel parking right next to the beach) you may also find areas of old staghorn growth covered in encrusting hard corals. It is usually teaming with smaller fish fry hiding among the staghorn rubble. A place we call the nursery.
Some of these areas are in as little as 8 ft of depth.
We usually kayak dive out to the 2nd reef buoys and depending on currents work our way north, south, or inshore along the various reef profiles. I have been diving the Oakland Ridges area for a few years now and find it fascinating.
Most cattle boats wont go to the area as it averages 20-30 ft depth with some areas like I mentioned, coming up to 8 ft. These -are- environmentally sensitive areas and are worth saving from any beach renourishment plans for the areas nearby.