Picture #3 that you posted on the gunboards forum, 1/1/2017 shows the difference between the original color and what's on there now. Urishi is a pretty durable finish, and not cut by mineral spirits or Murphy's oil soap. The person who stripped and refinished the stock probably used varnish or clear lacquer to finish it. Either "post original" finish can be removed with Formby's Furniture Finisher. You could then attempt to re-stain the stock closer to the original finish, and reseal it with satin lacquer.
That's quite a project,and I'm not sure I would do that, but rather leave the stock as it is.
Dean (the other one)
OFC-Orange Co. Ca Chapter