NASA has posted a large number of space and space travel related sounds on their website. The library includes lots of iconic astronaut communication clips. According to this article
you’re free to use all of these sounds as you wish, because NASA’s own audio isn’t copyrighted. It’s meant to be a public service to the American people of their taxpayer-funded government program, but that extends to everyone. There are some restrictions – not everything NASA publishes is covered by the same license [...]
So have fun with these sounds!
Redditor sbplat, and fellow booth junkie Will Irace reminds us that if you are on a Mac, or Linux Machine (Windows users would need to use cygwin) there is a command you can issue from terminal to download all of the sounds to your computer:
<code>wget -r -A "*.mp3" -w 30 http://www.nasa.gov/connect/sounds/</code>