yeah, them journals look pooched.
400/400 on a bore & hone sounds a little high to me, but maybe i'm wayyyy out of touch. i'd ask them what they'd do a crank for-- it's likely gonna need to go 10/10 so i don't think you'd be able to polish that out.
if they want a grip of dough on the crank i'd poke around for a production machine shop or a crank grinder, i don't know (exactly) where you are, but maybe a trip to a larger city with more industry might be beneficial in regards to machine work.
2nd hand cranks are always a gamble, but maybe between the classifieds here and book marketplace, offerup, etx you can source something.
how's the cam look? and the heads?