I have an Itoya 13x19 (a3+) folder that I love! Here's a link, I'm not sure why this one comes with stickers.
ITOYA 13 x 19 inches Original Art Presentation Book/Portfolio- for Art, Photography, and Documents - Pack of 2 + Scrapbooking Stickers 4 Pages of Emojis, Quotes, Letters & Numbers https://www.amazon.com/dp/B07M7PPDWX/ref=cm_sw_r_apan_glt_fabc_Y06B5T168ZAN726H2Z0T?_encoding=UTF8&psc=1