Ex-Revenue car outside Missoula

My guess would be a 36 foot, 40 ton, double sheathed, wooden boxcar with 6 foot doors.  I have seen the exposed vertical end wall reenforcements and small metal sliding lumber door befor, I am going to guess Mt Vernon Car Company. Another guess, built 1910 to 1925.  The metal roof may be a retrofit.  You might still be able to read the reporting marks inside beside the doors up high.  Tough to restore with so much of the heavy metal stripped from the car.  Thanks for posting the photos.

Just by eye it looks like a 40 foot box car to me. I would guess pre-USRA era.  It may have had a truss rod underframe.  I agree with the identification of the lumber door on what was the A end.  They were common on box cars serving the pacific northwest built prior to WWII due to the use of balloon framing in wood frame construction in the early 20th century.  The car also looks to have a radial roof, an NP hallmark.