I'm from Sabine Pass and I've been metal detecting before on McFadden beach. You can hunt the water line but not the dunes. There used to be a spot that would produce lots of old coins but none that were worth much, but it was near the dunes. I hunted out there for years and one day a Park Ranger told me not to hunt the dunes or he'd give me a ticket. That ended my McFadden beach hunting.
In the past 3 years we had Rita and Ike blow through and I would imagine anything that was on the beach is either out in the marsh or now uncovered. Last time I was down there you couldn't drive to the beach due to the highway being washed out.
All of the yards, like my parents, are now full of junk from the storm. I do know of one location that used to be where the bars and hospital were located in the 1800's that has produced some nice finds (mostly bottles). The problem is that is lies in the marsh and I doubt you'll want to wade out there with the gators, snakes, and mosquitos out. You also have to catch a low tide and a brisk North wind, which means you need to be there in December/January time frame.
I wouldn't waste my time on the beach but you never know.
