Original or reproduction balloons for Lionels postwar Target Launching Car and the recent reproductions of these cars can be expensive and a balloon only lasts for a few days once it is blown up.
Recently I have found packages of “water bomb” balloons being sold at stores like Wal-Mart that are the same size as the originals and function just as well. I purchased a package of 80 balloons for $1.99. At this price I don’t hesitate to blow up balloons for my kids or visitors to my layout who want to play with the car.