Looking for a pattern

Hello- I am new to this group. I do counted-cross stitch, needlepoint, and knit and sew. Anyway, I found a counted cross stitch canvas at a thrift store. It has a design printed on it but the center part is blank so I imagine that would be filled in with stitches. I bought it for a quarter hoping that I could find out the manufacturer and write to them for instructions on how to finish it. There is no name on it anywhere...I guess this is like a needle in a haystack. The picture is of an old mill with the name "Sullivan's Famous Flour Milling Co." on it. The back ground is mountains and a stream. The sign and the water wheel on the mill are printed on. The only blank part is the mill building. Does anyone have any ideas on how I could finish this? Thanks- Judy