What is the age of a Ranger shotgun that says Browning patent pending with a number of 31291 and where do you find parts?

We need more information to provide an age of the gun; Such as Model number and type of action: Pump or Auto. Most of these clones were sold by Sears & Roebuck. They are primarily utility guns and have little or no collector value. Condition is important to value a gun, but there is little difference in price for most of these. Pump guns $100-$250 Autoloaders $200-$350 Add 20% for near new condition / Detract 20% for guns with recoil pads or poly chokes.