I scored this vintage Co2 pistol at the Gettysburg Gun Show for only $40.00. So far I have found that Challenger Arms was in operation at Los Angeles, California from 1949 to 1951 making a side lever pneumatic pistol. Goodenow Manufacturing Corporation in Pennsylvania produced this Co2 version from 1954 to 1958. It uses 8 oz. seltzer bottle chargers. Is anyone familiar with this pistol? It is in excellent condition.