Something to keep in mind about shipping the 73 to the lower 48. The White Pass shops can do the work.
But, if you've ever been to Skagway, it is REMOTE. Everything has to be shipped in. Everything.
It might be more cost effective given the nature of rebuilding a steam locomotive these days to ship the entire locomotive out to be rebuilt.
For example, need to machine a replacement part from scratch?
Fine.
Don't have the right piece of stock to start the small project with?
Not only do you have to buy it, it has to be shipped to Skagway, before it can be machined into the needed part. Need a spring? Same thing.
At least a metal fabrication shop in the lower 48 would have the needed materials, or said material is a phone call away. Two days at most and your machinist is busy fabricating. Skagway? It could be six weeks before you get the material.
Given the fact there is always a surprise when a steam locomotive is opened up, I can see why a busy shop located in such a remote area might ship the 73 south. The cost of shipping the entire locomotive might be more cost effective when looking at the timeline to return the 73 to operation. Especially if the White Pass is advertising steam operations for the coming season.
Just a thought.