@hawk, serious but not unsolvable.
I would go with CROSSBOLT,
IF, I would be 100% sure this flakes are from this motor. Did you use it for your HONDA too? Or is there any chance from another source?
Anyway, changing crank bearings is not a huge deal. You would need a few gaskets, oilseals and bearings, which are Norm pieces.
If you can do it on your own, it's economically feasable, if done in a workshop, with cylinder removal and gaskets, not.