I think you must do an overall assessment of the actual out of roundess condition and the straightness.
Do you have internal tray support rings? If yes, things are even worst.
ASME Sec VIII Div.1 allows 1% dia for out of roundness and 2% for nozzles section. Use those figures to evaluate your...
Try Time of Flight Diffraction (TOFD).This ultrasonic base inspection was developed for in service inspections to monitor crack growth to maximise the usage of that component.