A couple of good suggestions are the following
Huckleberry Railroad in Flint....couple of the guys frequent this board. They have 2 3-foot steamers, including ex D&RGW 464.
Omaha Zoo Railroad...Authentic ex-Austrian Tank engine, that I have seen. Really makes some noise on a steep grade...Kevin Bush might have images(we only have video).
Dollywood near Gatlinburg has authentic steam as well.
Tweetse...not sure if its an amusement part though.
Steamtown...National Park, for amusement???
Greg Scholl