I've been listening to Apollo 13 audio files posted on Archive.org.
Besides the well known EECOM loops already published in Sy Liebergot's book, on this site I've come across some interesting Apollo 13 *simulator* flight director loops in file 795-AAB.wav
There is a lot of dead air but at time indices 7min:14sec, 08m:00sec, 09m:49s, 10min:14sec, 11m:10s and so on, however long you care to hear listen, you can hear them debrief over a simulation. Further on you can hear them perform actual simulations of various failures such as CDU bit failure 180 degree error, etc.
Some discussions at 1h:00m:44s+, 2h:29m:50s+, 2h:45m:00s suggest this is a simulation.
The description in the metadata catalog PDF doesn't mention it as a simulation. And the date given in the metadata is 17 April 1970 which doesn't make sense since that is the day Apollo 13 returned to earth.
I can recognize the voices of Milt Windler as flight director and John Aaron as EECOM. If anyone knows the other voices, that would be interesting. Based on conversations, Charlie, John and Jack are referred to by the CAPCOM which I believe are the backup crew for 13 (Charles Duke, John Young and Jack Swigert, before Jack was swapped for Ken).
Be warned, the posted file on that site is quite large to download (1 GB).
Hopefully they will post compressed files in the near future.