I've seen them go in the $300-$600 range for that age, and 85% or so condition. Some may ask or get more, but $500 is about average for better condition used guns of that vintage. Yours may be on the better condition end of the scale, and may bring up to the $600 range, maybe a bit more. The post war carbines are pretty similar, yours probably has the long wood fore end and isnt drilled and tapped for a receiver sight, tho I can't tell from the pictures.
The common sources for Winchester dates can be up to 4 years off, but in the age Patsy's gun is, they're probably pretty close. A letter from the Cody museum is the only way to be sure, but in that age range, there werent special order guns, and the exact age won't make much difference in value, so a letter probably isn't practical.