PASTED FORUM POST:

I've uploaded the thing that everybody wants from AST...in USB Bootable form  It's the MRI diagnostic software that they run at the apple store in front of you. Restore the image to a USB drive and boot from it.

The first one should work on almost everything up to 2012 Retina models. The 64 bit one is for some newer 2013 and up models with retina. Not exactly sure which ones but try imaging each one to a USB and see what works for you.

Please note: This does not work on the newest models which require the cloud diagnostics

past-2012: MRI_2012.dmg
2012-onwards: MRI_2012_64.dmg