Well, portable devices tend to attract scratches so this is unlikely to be the last blemish. Personally I wouldn't worry about it but there's nothing wrong with wanting to keep your stuff pretty. It's pretty unlikely you would get an exact paint code since it's probably not common knowledge even within ASUS. I haven't seen any product designers visit this forum.
You could always get an approximate match. With such a small area it would probably blend in. Or you could just do the whole thing in a custom paint scheme.
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A bus station is where a bus stops. A train station is where a train stops. On my desk, I have a work station…