CA M15A4 Charging Handle part

[Occers]

Hi there, a little hard to describe what i've broken but here goes!

Inside the reciever, the charging handle that gets drawn back to reveal the hop up chamber, has a black plastic "L shaped" part screwed onto it.
This piece of plastic draws the mechanism back, and then pushes it forward again when the charging handle is released.

I've broken it.

I have also wrecked the spring on the charging handle too, but managed to bodge that back to working using a doubled up royal mail rubber band. Crude, but it works (and i have spares).

I need another one of the bits of plastic that screws into the side of the charging handle, does anyone know what it's called, have one, or know where i can buy one????

I've posted this in the spare parts wanted section also, but thought i'd increase the chance of someone just knowing what it is i've broken by posting in here too!

Thanks in advance!