"High Road To China" was actually produced by China-based Golden Harvest Films, not CBS. Warner Bros. did indeed have theatrical rights, and for a time, home-video as well (don't know if they still have home video rights). The television rights are currently held by ITC/Carlton America. So I seriously doubt Paramount would have home video rights, unless Lions Gate would now have them.
Just saw this on one of the movie channels (ie-HBO,etc) and would love to see this movie released on dvd. Although, judging by the version I saw on tv. The picture needs a lot of cleanup.
I wouldn't mind seeing High Road to China paired with another Tom Sellick vehicle and a fine period piece, Lassiter. I haven't seen either film since they were released theatrically. Lassiter I get a kick out of seeing Jane Seymour sprawled out nude across the bed chattering on obliviously while gnawing on a chicken wing -- or was it a drumstick.
I used to watch both movies a lot when I was a kid, since we had friends in the states recording stuff for us when we lived in Germany, and those were a couple of the films we got, partially because my mother was a big fan of Magnum PI.