http://www.histandard.info/manuals/sears/pashotguns/index.html
Marlin High Standard made the Model 75 20 ga semi-auto shotgun for Sears http://www.histandard.info/PDF/Sears%20Shotguns.pdf
$125-$175
choke of sears model 20 12 gage plain barrel shotgun has 3 stars on barrel
I bought a sears 684 shotgun (12 gauge) at sears around 1979 , for $ 99
http://www.histandard.info/manuals/sears/pashotguns/index.html
Needs to be checked out by a gunsmith.
Most likely it was Sears in the late 20's
$64.95
Your 12 g pump shotgun was made for Sears by the High Standard Company- it was their Flite King model shotgun.
The Sears Roebuck Model 20 12 gauge shotgun, serial number 5832006 is valued at $200 in very good condition. It good condition, it is valued at $125.
http://www.histandard.info/PDF/Sears%20Shotguns.pdf
100-300 USD