Here is a typical Hex.
|Dungeon Geomorph B04|
Doors would be handled by counters placed at the appropriate spots (3 on this one). The "?" would be revealed by random generation when you came into Line of Sight of any of the 3 hexes it is touching.
I can easily create these now that I have a process down to do so. I settled on 3/4" hexes so that each Hex fits on a single A5 sheet for printing purposes.