I am not aware of us stocking a similar switch mechanism.
Replacing the switch mechanism requires electrical work and is not a D.I.Y. project.
Let me mention a couple of our knowledgable members @bruce93 and @HandyAndy. They perhaps would know where to get a replacement switch or they might advise that contacting an electrician is your easiest option.
Please let me know if you need further information or had questions.
i don't recall ever seeing one at bunnings, and i don't have any experience with window shutter controls personally,
however, i would highly suggest contacting a local electrician, or at the very least speaking to the (or any) window shutter manufacturer/installer. this would likely be a proprietry product, or something that can only be purhcased at a window shutter manufacturer or electrical wholesaler.