The Israeli vessel that was hit was no patrol boat. It was a Saar 5 corvette, one of the latest and largest vessels in the Israeli Defence Force, and a ship with a very high degree of Stealth technology built into it.
For its size, the Sa'ar 5 Corvette design claims the lowest acoustic, infrared and radar signature.
It wasn't hugging the shore either. It was a full 10 km off the coast. The Egyptian merchant vessel that was hit by another missile launched at the same time was 60 km off the coast.
As for the missile that hit it - few such have a range of 60km. This appears not to have been an old HY-2 "Silkworm" or derivative, but the far more deadly and effective C-802 "Saccade", derived from the C-801 a 20% overscale copy of the MM-40 "Exocet".
The French supplied the Chinese with the drawings for the MM-40 some time ago, knowing the Chinese didn't have the capability for making such fine precision machinery. Close, but not quite.
So the Chinese built one 20% larger, with 20% greater tolerances, something they could do - to French chagrin. That was the C-801. They then built a far more capable version, powered by a small turbojet rather than a rocket, with a greater range, well over the 45 km of the C-801
The Chinese are known to have sold this technology to Iran. And it's not simple, to keep a missile system like this running requires a highly trained crew, spares, a large infrastructure. Unlike the "Katyusha" rockets, this is no "aim in approximate direction of enemy, light blue touch paper and retire immediately" weapon, it requires highly sophisticated fire controls and radars. It's also something not easily put in the back of a pick-up truck, it needs specialised vehicles.
In the 1983 Falkland war, the British found MM-38 Exocets launched from land very difficult targets to pick out of the land clutter background. It was on June 12th 1983 that HMS Glamorgan was hit by an MM-38 Exocet, aft in the Hanger Bay. The usual tactic is to turn away from a missile that's detected, but insufficiently localised to fire at it, and rely on jamming.
A similar thing may have happened to the Israeli vessel. One missile was jammed and went seeking other victims, the other hit the hanger bay aft.
The point is - this was not a misile from Hizbulla. This was a weapon from Iran.