Over/under doors are double-doors that are stacked as a single piece. They are skinnier and taller than a pinball door. They appear on video games starting around 1982. Coinco, Coin Controls, and Happ have made over/under doors.
Note that inserts, buttons, and internal brackets tend to be shared with similar parts from the same OEM. That is, you can scrounge Coinco parts from an over/under door to fix your pinball-style door, provided they’re all Coinco.