Vintage Beatrix Potter Mouse print—yellowed but in original plastic wrap

This Beatrix Potter print of Hunca Munca mouse is at least or about thirty years old, by my guess. It is yellowed with age, I’m not sure if that’s fixable or not. It’s still wrapped in its plastic, with label/price tag at back. The size looks to be 8 inches by 10 inches. I’m totally unsure of an original price!