A bag of butterbeer caramels, a bag of candy corn, a handmade card with a pencil and watercolour drawing of a pumpkin on it, and a small bottle of murtlap essence, taken from June's potions supplies. The inside of the card reads:
Neville,
Happy Halloween! Have a lovely (and not too spooky) day.
Sincerely, Your secret friend
P.S. As you likely are aware, murtlap essence is good for soothing abrasions.