The locomotive that (I believe) stays foremost in my memory as a 3-year-old in 1945, is the lighter 4-6-0 J-25, as shown in the above picture. The heavier 4-6-2 Pacifics also ran past my window (above indicated far left), but my recollection seems to be more of the smaller engines.
A Lehigh Valley J-25 fresh off the assembly line, set up for public viewing.
There is no available J-25 HO scale locomotive, nor is there any 4-6-0 locomotive model that even looks like one. The only production HO scale J-25 model I ever heard of was one custom made by Dave Grover of Eddystone Locomotive Company a few years ago (seen below).
If you compare this with the prototype above, you can see it is a very good re-creation and would certainly meet anyone's expectations for an accurate operating replica of the prototype. He built this engine on a Bachmann-Spectrum 4-6-0 locomotive (below), and while no doubt this was the best place to start for a highly skilled custom builder, in terms of running gear, boiler, mechanicals, running properties, etc., in its "native" form the stock engine looks a far way from a J-25.
The Bachmann-Spectrum 4-6-0 (above) has numerous components that do not match the J-25, including the headlamp, smoke stack, piston housing, and, most obvious, the domes (see below).
But this presents no great obstacle to the modeler with the skill and inclination to base a J-25 re-creation on a basically correct structure, wheelbase and quality. The task is made easier by a pair of 1940s photographs, taken just one stop down the line from New Woodstock, at DeRuyter.... of the same engine...on the same day...from opposite sides! Note the field of daisies in each image.
Published in two different works on the LVRR Cortland Branch, these pictures of Engine 1150 are as close to a modeler's "walk-around" shoot as one could want to get. So nothing could prevent someone from making a 100% accurate model of this engine, if they were so inclined. Or they could pay many hundred dollars to have someone make one for them.
It may be heresy to suggest making a model of an engine we have perfect data on, that is less than a perfect replica. The word "prototypical" usually implies an exact copy.
But my layout is based on a prototype memory from almost 70 years ago. And I am as interested in recreating the experience....the "look and feel"....as I am in creating a totally accurate historical reconstruction. In the layout itself, the only way to approximate the look and feel was to research what structures would have been there in 1945 and what they would have looked like......and the operative word there is "looked like". Many of the finer details a three-year-old would never have remembered. And the same applies to the J-25.
Since there is no off-the-shelf 4-6-0 locomotive that could be made to "look like" a J-25 without a great deal of difficult kitbashing requiring a great deal of skill, I looked to other HO scale engines that looked more like the J-25. And here I discovered several that seemed pretty close. All are 2-6-0 moguls which could, with minimal modification, stand in as near doubles for the J-25.
Let's try some match-ups with available stock HO scale moguls.
The Bachmann 2-6-0 above seems a close match. The stack needs to be shortened and the forward dome and bell switched places, and perhaps the domes are a bit flat-topped. And the "cow-catcher" pilot is wrong. But other minor differences seem easy enough to fix with some applied details. And the coal tender is a good duplicate of the one hauled on the Lehigh. However, the rear driver is a bit too far forward, being ahead of the leading edge of the cab.
Perhaps a better starting point is another mogul, sold by IHC (below).
The headlamp is in the right location, the stack is shorter, and the domes seem more rounded, like the J-25. Plus it does not have the cow-catcher pilot, but one closer to the prototype. However, it only comes with an oil tender. I have this engine and with its tender pick-ups it runs great, but one would minimally have to swap out the tender to even approach the J-25. Plus the forward dome and bell would have to be switched. But the rear driver is closer to the correct position (see below).
If we compare the engine details with the 1940s prototype, we find some good matches (above).
Of course the major mis-match is the leading truck, which should be four-wheeled, not two-wheeled. Perhaps a modification would allow a proper truck to be attached here. That option is yet to be explored. But it seems the off-the-shelf IHC 2-6-0 mogul (below) is a very solid starting point for a "poor man's" LVRR J-25. And even running the stock engine, with a swapped out tender and a little weathering, would be a good approximation until something better comes along.