I finally had time to unpack, inspect and clean them.
The person I bought them from painted them red. Unfortunately the piston and dust boot were not masked off before painting.
I cleaned them off pretty well using a kitchen sponge with Simple Green.
The pics show what I was able to remove so far.
I'm thinking I should follow the procedures in this thread to change out the dust boots and fully clean the piston tops before using the calipers.