I was finally able to ID Margot’s main pieces from this look so I can now post!
While at the beach with Tom, Margot wore a Fella. “Hunter” Bandeau Top. The front knot piece is in the shade Spiced Orange and available for $143 or 4 Afterpay payments of $35.75.
Margot wore a pair of Palm “Baja” Bottoms in the colour/print “Floreal”. These are priced at $110. Thank you @skriverscloset for this ID!
Margot covered up a bit more while at the beach wearing, what I think may be, the Matin Linen Wide Leg Pants in White. They’re available for £264.