I don't know where you got your numbers, Lee, but it does not cost $10,000 to fill the tender. The current price for coal delivered to Indiana is around $195 per ton. 22 tons at $195 per ton is only $4,290. If fuel prices continue to go up, that price will, too.
Now...let's put that number in context. The 765 burns a ton of coal every 10 miles. That means that just the cost of coal is $19.50 per mile! It takes a LOT of money to operate a big engine like the 765.
As Steve Lee, former head of the Union Pacific Steam Department once said, "Steam engines don't burn coal or oil. They burn money."
And I can assure you that Ichabod is just kidding about hacking the speedometer. The 765 is equipped with a GPS speedometer anyway.