I like Hayden's (
@Hayden Watson ) idea of drilling an oversized hole and tapping for a larger machine screw.
But first check out this pic.
This is looking up at the starboard side deck joint area at the forward bulkhead. The red and black cables are for a windlass. The silver dot above the red cable is where one of the machine screws for the pulpit base pokes slightly through. If this machine screw stripped I would put a longer bolt through and put a thick large nut on it.
You might be able to do the same depending where the machine screw can be reached.
Hard to see in the pic but when you take a close look you can see the thicker area where the metal plate is embedded.
Edit: I was writing while Gene posted. Based on the thickness I see I'm guessing the plate on the C30 is 1/4".
When I rammed my pulpit into a piling the front pushed down and the back pulled up, pulling a few screws out of the plate. I'm glad they stripped out rather than pulling up any fiberglass. On second thought I would rather drill and tap before putting nuts underneath.