Hand cranked Leach siren

[Leach]

My first post! I have just found this Leach hand cranked siren. I believe it is a pre war model.

It is missing the control from the handle to the side vent, so I am keen to take it apart and rectify this.

Does anyone have any exploded parts diagram for this or a similar siren please?

Any additional information regarding the siren would be appreciated too.