'Rewire' entry sensor to reverse state shown

I have a security application where I would like to show an alarm state when a bolt (not the door) is open.

I can mount an entry sensor so it makes contact when the bolt is open, but need the state to show 'open' when it would naturally show as closed.

Is it possible to achieve this, say by simple rewiring, and/or replacement of the (I presume) reed switch?