I have a set of Ithaca NID 12 ga barrels.They are 30 ",left barrel is .680 ,rt is .700.Ser # 4347xx,"TP stamped on forend lug,FI on barrel piviot.I was told they are B grade.There was a coating of rust freckeles on barrel that were oiled and possibly steel wooled,but not scratched.On the right...