I consult the Faculty secretary who forwards the issue to the Pro-Proctor for Ceremonials. The message is, "as a Professor here, you are entitled to an MA Status gown (without strings)".
I look up gowns on the University Shop website, and they have such a variety that I get dizzy. You can rent a gown, and you can buy one for a substantial, but not unsurmountable sum. I have many times, letting my imagination flow beyond all reason, pictured myself in a gown.
By the way, I have worn an academic gown once. When I had by inaugural lecture at the University of Worcester as an Honorary Professor, the person in charge told me that they couldn't find a robe from Stockholm University to rent for me. She was astonished when I told her there wasn't any such thing. They got one for me anyway, from Coventry as it turned out, and lo and behold! it was blue and yellow, the Swedish colours.