I just finished painting ~100 varying sized lead eyes and I used the "comb" method. I purchased a package of various sized combs (8-10 combs)from the Dollar store for $1. I spent ~15 minutes inserting the eyes into the tines of 3 combs and then I spray painted the eyes. Using a piece of string tied to the combs, I hung the combs/eyes up to dry. After drying and while still in the comb, I painted the pupils with a dowel sized to the pupil size I desired. After this dried I again spray painted the eyes with a clear protective coat and hung them up to dry.

This whole exercise took ~ 1 day considering the time allowed for drying. Actual work time was 15 minutes to insert the eyes into the comb, 5 minutes for each spray paint job and 15 minutes to paint the pupils. So the total time spent on the job was ~45 minutes.

Hope this is helpful.