Masters Hats for large head?

[Cal Ripken]

Does anyone know where I can find a masters hat for my big head? I wear a size 8 fitted hat. None of the one size fit all hats with straps etc fit. At the merchandise shop on the grounds of Agusta, do they sell fitted Masters hats up to size 8 or 7 7/8 ??

Thanks for any help you might have!