Bill,
I was told that we were targeting 1910, or thereabouts. I looked around at pictures and put together things that looked like they were from that period. This includes my bowler hat a la Ira style, which I now consider a Ira Memorial. That I created from a regular black hat with an appropriate brim that I steamed and reshaped to the bowler style. That being said, I know Ed Lecuyer found a source that looks very authentic down to the proper buttons for the suspenders and shirt materials.
Now that my face is worn and creased I know when I wear my bowler hat I get my photo taken a lot when I am brakeman on the passenger trains. Baseball caps weren't used back then. Newsboy hats were the most common.
There are several conductors outfits in the house if you want one of those.
On days that we are making photo runs, or tourist visitor days I try and dress for the duty that I have for that day, brakeman, conductor, fireman or engineer.