Soak everything rusty with WIPE OUT bore cleaner and genty rub with oooooo steel wool.
This won't harm your blue finish, but it will dissolve the rust down to the shiney metal underneath in less than half an hour.
The shiney spot area should be cleaned with alcohol and cold blue of your choice applied.
Don't try to clean up the area around the spots, other than to remove the Wipe Out residue, so the cold blue will have the desired affect. You will likely need to make several applications to get the proper blend.