It is interesting what another set of eyes will see ! I sat here with those three signs in front of me and did not notice the 1957 version did not have a dash between Fire and Chief.
I have several of these signs. They are very common with dates from the 1940's, maybe earlier? threw the 1960's.
I put the 1990's repops on pumps I am getting rid of. They are very good quality, the right size and inexpensive. For the pumps I keep I put originals on and if you are patient you can pick them under market value.
Andy Rooney sign Co. made a porcelain repro but it is smaller, and has a sandpaper feeling back, again good quality.