I was at my local Target and I saw a shirt that would be an ok Alt for the Miss Selfridge shirt. It is online
here. The sleeves might be a little shorter, and the drape in the back not as long, but the color and cloth are good matches and the pocket is in the right place. For some reason the web site says it's not in stores but I have a feeling the mean in "all" stores as mine has it. I hope this helps someone :)