El Senor Coke,
At the risk of falling flat on my face, here's how I figure it ...
The WW&F is estimating about $200k to restore their #9, which includes a new boiler. I also seem to recall the estimates for the new Lynton & Barnstaple 2-6-2T replicas that the ffestiniog and L&B preservation groups are currently constructing - come in at about 300K pounds (so assume about $500K U.S).
Assuming a 3:1 cost ratio between refurbishment of an existing locomotive and new construction of a similar locomotive. This would net about $600K for a new Portland, which might be a little high (especially since we already assumed a new boiler) but not too ridiculous.
Working in the other direction, an SR&RL #24 is marginally bigger than an L&B Manning Wardle and also has a tender, so let's guess a $750K price tag to build one from scratch. Divide by three for a sanity check, yields $250K to restore say one of the Brazilian six driver locos or perhaps a Cuban n.g. mogul. (Again assume a new boiler.)
Seems doable ...
One final sanity check. One of the Cuban n.g. consols ... just a tad smaller than ... say ... a C-17. By the above thinking, I would guesstimate about $300K (including a new boiler). Given the calculations of a dedicated (and I sincerely hope successful) group of railroad preservationists in ... say ... Durango ...
How bad did I step in it?
Grins and Best Regards,
Glenn