How long are you going for? Our family of 4 can do 4 days on our water tank, so the water being off wouldn't be a problem. mind you October isn't the winter!

The info in my book here says the aire in the disneyland main car park is open all year, space for 50 motorhomes.
Showers and loos closed 7pm to 8am but no water or chemical loo facilities at any time!

However just up the road in the Esso fuel station outside the Hotel santa fe. There is a service point for water and loo with tokens to be bought from the kiosk 4 euros. It also says it has FREE overnight parking for 6 motorhomes but you must ask permission in the kiosk.

If your up for a 25 minute drive, St Cyr Sur Morin is just about the closest place with an aire which is free and in a lovely village.