Go ahead and look for the green fabric. I was able to match a yellow to an old quilt top to square it up. You can't even see any difference. It was a perfect match 50 years after the quilt was originally pieced. I found it at JoAnn's. Your fabrics look like they are feed sack prints. My vote is for leaving the wheels intact. Think of the hours the sewer put into stitching them together. It will be beautiful whatever you decide.