I am pretty sure if you knock on a door this time of the year almost all farmers will let you take a doe. Late Buck tags are done and for the most part faming is done till spring.
Don't just knock on any door, look for the ranch house that has all the equipment, elevators, etc. etc... alot of houses are rented out in the area and those people will turn you away because they cannot grant or deny you permission.
Good Luck