To expand on my earlier post:  I would not put your request in writing.
I am not suggesting anything shady.  Many people despise paperwork.  If
you request a donated display item in writing, you may be forcing them
to fill out a whole bunch of forms.  Also, in a lot of businesses,
appearance is everything.  If the donation is down on paper, the home
office may later call it into question.  'Everyone' 'knows' there is a
lot of waste but they cannot ignore it if it's down in black & white.
(Donation=waste.)