Make them yourself! You'll get the SPF of your choice, and they'll cost MUCH less. I like these because the kids can handle them easily, and they manage to avoid their eyes with wipes. Here's how:
Buy a big box of baby wipes (any kind with a box-style lid -- no pop up style), and let the lid stand open a week or so until they're completely dried out.
Remove the wipes from the box, pour in a whole bottle of sunscreen, and mix well with some water (let's say 2/3 sunscreen and 1/3 water).
Put the wipes back in the box, and separate them a bit so that the sunscreen permeates each wipe. Being dry, they'll suck up the liquid sunscreen.
If you need to carry just a few, put them in a ziplock.