VERY small and short outdoors Santa Monica wedding. Permits, costs, experiences?

We are already married, but we want to have a little ceremony to exchange rings since we didn't get to do that at the actual wedding. It's only going to be around 8 people (including us) and we are having a friend say a speech and make us exchange rings, and another friend probably playing accordion. No chairs, nothing fancy, probably around 10 minutes long, at dusk. Do we need a permit for that? We were thinking of doing it at Pacific Palisades Park in Santa Monica or down at the beach. Suggestions about other places are also welcome.