Scheduled times between Europe and the Pacific Coast in 6/62:
LAX-LHR-- PA 3/wk 10:30, TW 2/wk 11:55, BA 3/wk 10:30
LHR-LAX-- PA 11:35, TW 13:12, BA 13:00
SFO-LHR-- PA 1/wk 11:25, BA 2/wk 10:30
LHR-SFO-- PA 11:20, BA 14:05
SEA-LHR-- PA 2/wk 9:30
LHR-SEA-- PA 10:25
LAX-ORY-- TW 2/wk 11:05
ORY-LAX-- TW 14:37
(All these are based on an 8-hr clock difference to LHR and 9-hr to ORY-- I guess they had Summer Time in Paris?)
All those flights are shown in the Quick Ref OAG as nonstop, which presumably doesn't mean a whole lot. Nobody had 707-320Bs by then, did they? Air France got their first -320Bs by early 1963, and they probably didn't start LAX-ORY nonstop until then; any reason to think they ever tried to fly JT4As nonstop in either direction?
FWIW Flight for 23 March 1961 says BOAC flew LHR-YUL-LAX; in 1962 The Aeroplane mentioned that about 90% of BOAC's LAX-LHR flights until then had been actual nonstops. Also, PA made the first known jet nonstop LHR-LAX on 1 Jan 1961-- average headwind component during the flight was zero, it says, but they departed with full tanks, 155000 lb, and arrived with... 13000 lb I think it was.
While you're wondering about such things, give a thought to El Al's 707-420s TLV-IDL. Anyone know how often they did that nonstop?