I doubt if you'll have any problem getting a permit for Marion Mountain. I don't think there is a quota for that trail, but you need a permit from the State over there. The State Park Headquarters is in Idyllwild, and they do have self-issue day use permits, but they don't always leave them out. I'm pretty sure the State will let you get a permit the day before your hike, but I don't know if the office will be open on the 4th.
I've never been asked to show a permit in the State Park on any of the south or west side trails, so if it were me I probably wouldn't even bother. That being said, I know several people who have been asked for a permit in the State Park by a real ranger, and those cats are serious. They can issue a citation.
Stone Creek is a nice campground. Enjoy. Azalea and columbine in bloom. Report back if you see any Lemon Lily on the trail.
