I would suggest that you get the oil analyzed BEFORE talking to your dealer about possible major engine damage conditions. It's been my experience that knowing as much as possible before going to a dealer about potential engine or transmission replacements allows you to present facts instead of guesses. I also suspect that a previous owner of your car probably had it highly modified and probably raced it.
Thus the suggestion for an extended warranty is a good one. I would suggest either getting an extended warranty or trading your Fiesta ST for another. Because if you really did see copper flakes in your oil I foresee the need for an engine replacement sometime soon. BTW, back in the 70's and 80's when I was hands on building engines the main bearings did have a layered construction with copper constituting one layer. Not sure if engines today still use that style of bearing construction but if they do copper in your oil is an indication that your main bearings, and the crank journals, are shot.
BTW, back when the SBC was king the typical response to worn out main bearing was to pull the engine, tear it down, check the crank for damage, and slip in a new set of bearings for the rods and crank if the crank journals looked good. That is about 2 1/2 hours on the engine assembly and with the help of a buddy about 4-6 hours for the removal and install of the engine. Basically you could start at 8:00 AM and be kicking back at 4:30 popping the top on a beer. One plus for those antiques is that they were easy to work on, something that cannot be said for our cars today. Heck, was a time when I could pull the engine out of a VW Beetle in under 30 minutes.
Now we have engines and transmissions that take many many hours to remove and they also are hugely complicated to break down. Upside is the HP/CUI is a lot higher but the downside is that servicing these beast is a lot more complicated.