Jon,
Columbus Day Weekend is the last hurrah for regular operations on the Maine Two Footers. The exception may be Sandy River, they run "Ghost" trains at some point during October, not necessarily at the end of the month.
The WW&F has their Fall Work Weekend that weekend, with over 100 volunteers over 4 days Friday to Monday, usually laying or maintaining track, building buildings, etc. Regular train operations are Saturday and Sunday. We'll continue Saturday-only until the end of the month. See
wwfry.org Calendar for details.
The others are
Boothbay Railway Village, Maine Narrow Gauge, and Sandy River & Rangeley Lakes. I don't know their URLs off the top of my head, but a quick Google search will help. They should all have schedules available on their website.