In between the "JPEG" and "IMG" notation at the far right of a photo link you typed in ~original and the photo showed back up.
I did it hundreds of times at forums where I had done how-to
threads. I wrote PB and asked them to be reasonable for use in forums where no money was changing hands. Eventually somebody there listened to us forum users and imposed a $20/year fee instead of the draconian $40/month nonsense.
I paid the $20 so the other photos I'd either forgotten about or just didn't feel like fixing could be restored. But to be honest, I found sites like tinypix to be easier to use.