I am having difficulty in getting perforating gun 3 3/8" OD with a 3/8" wall material in USA, I am looking to buy ASTM A519 1518 Steel Tube, Hardness 28-32 HRC , yield 126,600 PSI, for the Gun Carrier or an altenate material is 4135 Tube, 31-35 HRC, Yield at 142,900 as per the lab results on an...