G.G.
Since it will be in October, have you considered having at a Pumpkin patch or farm? I'm familiar with Bengston's Pumpkin Farm and know that they do parties, but I'm not sure how that works for you distance-wise. I've been to kids' parties at pumpkin farms and they're great. Each kid gets a pumpkin, you usually get a private party room for food and drinks and it's a great fall activity for families.
We're planning to have our daughter's party at Pump It Up (very reasonable pricing and private parties) and I am pretty sure they have a location in Lisle. Best of luck--this is a great milestone.