Thank you, one and all!!!

Art stores have pre-primed masonite panels (for art work). I used one,
with an unfinished
frame of same size, to make an access panel. I glued together, painted,
and screwed it to the
wall. Might be tough to fashion it to fit your need, though. My panel
is in guestroom, next to
guest bath, and is kind of out of the way. I used brass screws with
little brass "o" rings to
pretty it up to fasten to the wall.