Need older version of Adobe Media Encoder CC 2017 for Mac

I have an older mac pro running OS 10.11 and we had Adobe Media Encoder 2017 running on it. I upgraded to a newer version of CC and it broke the older one and the new one isn't supported by this OS/hardware. The Mac Pro can only go to OS 10.11 so now I need to reinstall an old copy of AME 2017. Adobe won't sell it to me - where can I get it?  And yes - I am running an old trial of 2017 version but really can't be reinstalling it monthly. It's frustrating when you are willing to pay for software but the distributor won't sell it.

thanks!