And I didn't send you a standard size, but 333 dpi makes for some leeway. Can make a standard background of 8 1/2 by 11 without resizing the actual image. Can enlarge the image only slightly if you want landscape not portrait. The one you have is 8.08 inches W by 7.62 H, so close to a square!
Have resized 'not a quilt' t0 333 dpi (high resolution). It is 1.7e mb, so shouldn't try to send via ichc. Can you accept a file that big in your email? If so, send me an email, and I will send it as an attachment.