I got one of those "Atari VCS" consoles for $80, bought some RAM and an SSD and stuffed it in there, and now it dual boots AtariOS/stock and, effectively, as a Steam Deck.

It's not really the Deck's OS, but it boots right into Steam and has the same UI as the Deck.

Not a fast machine but it's fine for the RPGs I wanted it for.

And it's woodgrain.