I realize that this post is 8 months old, but I'll post this information anyway just in case the original poster is still looking for leads. I recently came across the website for McDowell Equipment in Sudbury Ontario. See the link below. They list quite a bit of used narrow gauge mining railroad equipment, in many different gauges including 24 inch and adjustable. (Click on "See More Mining Equipment" and then 'Locomotives/Railway Equipment".
I have no affiliation with the company; I just stumbled upon their website. And I have no idea how hard it is to import equipment from Canada but I suspect that you would need to get a broker involved.
As for the Toonerville Trolley I love it, and have been trying to ride every other year or so. I'm curious what kind of range those old battery-operated mining locomotives that McDowell has for sale might have (with decent batteries). As much as I enjoy the Plymouth diesel locomotives you currently use, they can be loud and the wind occasionally blows the exhaust back through the passenger cars. If a battery loco had the range to go the 10 miles or so needed for your round trip, that might be an interesting option. (I do realize that one of your primary locomotives was recently rebuilt. I'm just daydreaming.)
McDowell Equipment-Sudbury Ont
Edited 2 time(s). Last edit at 06/16/2020 04:29PM by wawatam.