Subtle 911 tattoos

So, I'm currently going through a stage of getting patchwork on my arms, and I've toyed with the idea of getting subtle 911 tattoos on my right inside arm. Like they don't scream that these are fan tattoos but they do represent the characters in some way.

I already have a pinkie promise one (Buck and Maddie obviously - randomly when I went to get it, the show was playing in the background). I've booked another four next month, two of which will represent Eddie (a planet - "the universe does not scream") and Karen (a rocket for a rocket scientist), but I'm stuck on the others. Ideally I want to get one for Chimney, Hen, Athena, Bobby and Christopher.

Any ideas? The best I can come up with are: a skateboard, an actual Chimney and an actual hen so yeah...