| I've got an ssie airbox you can borrow.
Now...re. the swinging arm....ya shudda asked and I'd have told you about them cotter pins. Mine took just a swift tap - as a matter of course I dropped the arm out so I could lubricate the spindle. I'm sure you will be able to get some cotter pins made up in an engineering shop. In fact I am doing that right now although I will be pushing my favours quotient to ask for more.
I can get a CAD dwg knocked up if you want. | 
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