Change "recommended" header size

Hello all, I’m tearing my hair out trying to resolve a problem I’m having. I’m running the theme “Winning Agent Pro” on Genesis Framework. I have a custom logo that I want to replace the header with. When I go to replace it under Header Image, the theme says it “recommends an image size of 300×80.”

The problem is that this size is MUCH to small for any custom logo/header. You can barely see my site name and logo when I resize the image to this size. So my question…is there a way to increase the recommended image size so that I do not need to crop it and so that I can add a larger header? Thank you in advance and I can also add screenshots if it helps!