I googled 12v limit switch and found this link below that you can copy and paste in your search bar. May need some fabriction however looks like it might work. You may find a better one if you keep looking on line. Or the one above from one of the vendors.
http://www.precisionproformance.com/ft1142.php
www.alibaba.com/product-gs/699...ical_door_limit.html
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