Mr W. Schirra wore an 861 in a straight lug case apparently. https://omegaforums.net/threads/national-air-space-adds-25-nasa-speedmasters-online.34736/
Well since current astronauts from different agencies still wear the watch on the outside of space suits and the watch was re certified in 78-80 for the space shuttle. I'm pretty gosh darn sure 861's have flown and been in space walks. Ther is also pretty good data that 1 861 went to the moon.
One 861 went around the Moon during the Apollo 17 mission attached to the heat flow experiment... After the 1978 tests, NASA received several 145.022 Speedmaster chronographs, among which the radial dial version (all 861 movements) http://moonwatchuniverse.tumblr.com/archive
That is 100% incorrect. They were bought through a procurement process - those of us at the Speedy Tuesday event in Bienne heard Jim Ragan talk about this at length.
From the dinner in Tokyo last year: http://www.watchprosite.com/page-wf.forumpost/fi-677/ti-1054643/pi-7607273/