Vaughan Williams, August 2, 1958, Tanglewood (Munch, Boston music director, 1949-62). NB, this was not the US premiere of VW8 for Ormandy had done that in 1956, a few months following Barbirolli’s Manchester launch.

Sibelius: July 30, 1965, Tanglewood (Munch returning as a guest conductor).

Letter from Sibelius to VW regarding the latter’s Fifth Symphony:

http://vaughanwilliams.uk/letter/vwl2042