I know that Lanchester! Seen it before, last I saw it ten years ago it belonged to British Saloon Car Club member Mike S., sounds like he's the one selling it based on his description and what I know about the car...
As I recall, it was displayed at either the 1951 or 1952 new car show in Toronto and that someone purchased it right off the display that weekend (as to my knowledge they never ended up selling cars over here), a fellow named Lloyd eventually purchased it (he was a guy known for finding rare cars), he almost never restored cars just found good new homes for them, he was the one who sold it to Mike... Definitely a rare piece!