[Jac Mac]

One problem with any 'metal making' in a freshly built engine is there is no sludge buildup in the pan or valley to entrap the 'metal' so its more likely to be circulated. If this engine had 50k miles on it you probably would not be seeing anything to worry about. Fit a magnetic drain plug and expect to 'see' a bit of 'fuzz' on it for next couple of oil changes, the amount should decrease over the next few changes, if it increases then you do have an ongoing problem. With your broken springs they would have been rubbing away at any contact points making metal in the process.