Does anyone know where to get a small remote control electromagnet to release a flap for a production box? Thanks -

Bill

You likely have everything you need in the junk drawer, except maybe the smaller insulated wire, available at most any radio-electronic store. A paperclip can be a switch, or a metal pen clip and a small tack.
If you are talking something for remote from say 5 or so feet away, then try bashing up one of those mini RC car things, the steering switch works well as you can laterally turn the "wheel: switch side to side for a contact.
k