They can also be made at DownTown Disney. There is a little stand near the Rain Forest Cafe.
They are a very inexpensive "memory". My Mom still has numerous from trips taken 20-30 years ago. You should see her face when we give her copies of her granddaughters.
I believe for 2 people and 2 copies...it's around $7-8. It's a few dollars more to add an additional person. Of course, you can purchase frames...etc
Enjoy