Likely originally contracted by Wallace & Smith of Milwaukee, Wisconsin. They were contractors for harnesses and other horse gear during WW1. The saddle is darker than russet, but not black. I entered the saddle in the Northern Wisconsin State Fair 2016 and it placed 1st in the Military division, and Best of Show in the overall antique division. This saddle has been thoroughly cleaned, oiled, and sealed with beeswax.
May have some blemishes due to age, but appears to be sturdy and solid. No wiggle in the tree, ripped stitching, etc. Shown on a stocky 15.1h paint gelding. Horse and other equipment are not included.
A few are listed in other auctions. The item "1918 McClellan Artillery Saddle (similar to Cavalry) WW1/WW2 Dark russet" is in sale since Friday, October 21, 2016. This item is in the category "Collectibles\Militaria\WW I (1914-18)\Original Period Items\United States\Personal, Field Gear".
The seller is "miss_jacks_black" and is located in Chippewa Falls, Wisconsin. This item can be shipped to United States.