Hello, I was hoping to get some help on these signs In terms of value and grading. They're 16' long and in two parts. It's hard to get a good pic of them because they're so long. No date stamp but it is stamped Reg. U.S. Pat. Off. These are porcelain. I can take more pics of course if needed. Thanks in advance for the education on these signs! For some background: I got them from an 85 year old gentleman who found them in the woods on his farm in 1963. There was a Richfield station in his town that had closed down, so these could be from there.