Need Help Identifying Garand Barrel ?

Purchased a Garand to go along with my WW2 bolt rifle collection about 2 months ago. It is SA throughout except the barrel... I've done some research online , posted the barrel markings on other forums and talked to Vets at local gun shows... No one can identify the manufacturer...Here are the stamped markings: 6535448 PS -1-58-X1 Most are saying not USGI... Jan,1958.. drawing # is right... THE Big Question is the PS ????? The TE is 1.5, ME is 3.5 , the bore is bright , Shoots tight groups.... Does anyone have a clue ???