well done @scifiwooter.
A door can be picked up at Lowes/HomeDepot with no holes for handle -- it's called a "Blank" -- and is typically a custom order.
you can pick solid core (recommended) vs foam, and flat surface vs all the options for routing, panels, etc.
I'm buying this 8Ft option and going for 36in blank. though I may browse a bit on craigslist for some reclaimed wood/etc.
scifiwooter wrote:Any door will work. A solid core door is probably best. Or make one. Having not installed one (but is in my future) if the current door is a 32, you'll want a 36 to overlap the opening. Anyone whose retrofitted one can chime in if I'm wrong on the door size.