Your best (and perhaps only) bet is to do it yourself. Wood is probably most easy to work with. The whole construction will be hidden behind the TV, so it doesn't matter if it does not look perfect.
There is the Mac Mini Cuff from Sonnet (
Amazon product page /
Sonnet product page), but it only supports VESA 75 and 100, so you'd have to construct an adapter plate. Some users have reported that it'd scratch the mini on insertion - and the price is comparably high.
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