have you looked into wholesale? i know places like Sam's (Walmart affiliate) and other public wholesale stores sell large bags of candy for less than regular retail so that might help your budget a bit and if you could get a local sponsor to agree to split the cost for a little advertising like the others have suggested you could have more than enough candy for halloween.

what ever you do, keep in mind that Hershey's has announced they will be bumping up their prices due to the higher cost of production, so candy is gonna get pricey the closer halloween gets.

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