Hi Chris,
Photo as requested. The stapler is 110mm long. Switch is old style push-to-make, (not a micro switch), Jaycar Australia P/N SP0710 or 0711 , mini SPST. Spring, anything you have but it IS necessary as the switch spring is not strong enough. Just make sure it sits on the switch and can't fall down across the switch lugs. Lugs bent outward 90° and switch fastened to plate (non conductive) with 10BA screws and nuts. Hack the staplers as needed.
Best wishes,
Robert.
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