How to get P5 running from a PS3 Disk?

Of course it can be emulated through legal means - you just have to dump it using a PS3 with custom firmware until someone generates an .IRD file for your disc so you can dump it with 3K3Y on PC.
Quickstart guide refers that "that you can only use this method [PC dumping] if an .ird file is available online for the decryption of the disc".

Note that in most emulators you end up needing the physical console and/or specific hardware to dump your games, and if you have digital PSN copies of games you end up needing a PS3 to dump them.

I understand that. I just hope to GOD that someone makes an .ird file quick cause I just dropped $50 on a PS3 copy for Persona 5 just for this.