What part is this called? (Pictures attached)
 

Hi guys, I am new here (great forum btw),

I have bought a headlight (used) and attached it to my car but then realized the indicator insert was missing. I thought it was simply a replacement bulb job so I did that but it wasnt working.

I don't know if it is more serious (i.e. wires missing or a indicator unit is needed) so any advice would be appreciated.

Here are the pics of the missing part, can anyone tell me the actual name of the part if it isnt just a bulb and how much they roughly cost?

Thankyou!