I don't typically send postcards, but I know that they aren't outrageous or anything. At Disneyland Paris, they were about 1 euro, which is about $1.25 each. There are also postcard books where you can buy a lot of postcards for a lower price. These can be found in various stores, but definitely for sure at Downtown Disney if you can't find them elsewhere.
I think it should be fine. Just know that they take a long time to get mailed because Disney only mails things from the park like once a week.
Our Authorized Disney Vacation Planners are here to provide personalized, expert advice, answer every question, and uncover the best discounts.
Let Dreams Unlimited Travel take care of all the details, so you can sit back, relax, and enjoy a stress-free vacation.