You could totally make the eye patches yourself and forget the hats.
Felt sheets are only about a quarter each. Buy 4 in black, a spool of elastic thread and some tacky fabric glue. I've sewn them before but glueing would be just as easy and last for a good while. Just cut out two patch looking shapes then sandwich the elastic thread between the two shapes. Put glue around the edge of both shapes and insert the elastic thread on each end. Press firmly, allow to dry. Done.
Herding my flock of 4 kids, all 12 and under.