Charles Dickens to [Henry] Austin [Jnr]
The text of this letter is published in The Letters of Charles Dickens, vol 10, page 80, 'from facsimile in the National Library of Scotland', which is a pretty sure sign that the original was not known to the highly-skilled editorial team, and a fair indication that any further copies of the letter coming to light may also be facsimiles. Given that the location of the original letter is not known, it is always possible that it may yet turn up.
It is also curious that this excellently-accomplished facsimile is of quite trivial content. This particular example was sold as an original by a leading auction house in 1992.

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