I already have LR5 (bought in 2013) running on my mac.
I am looking for a NON PAYING upgrade of this 5.0 version (no CC version wanted). I think I've had the 5.7.1 version running on this mac 1 year ago, but I erased my computer for other reasons and re-installed the 5.0 version I had on a CD....
I asked Adobe support which gave me this link http://trials.adobe.com/AdobeProducts/legacy/99CABBAC-C975-4A06-8D99-064C6871EE80/LTRM/5_7_1/osx10/Lightroom_5_CCM_LS11.dmg
I have installed it and then, I was no longer allowed to open LR. There was a licence error called :213:10
Adobe Support is not able to help me, arguing that the application is no more supported with MAC OS.