Reply to Painfully unquantized track

I've been wanting to remix this song that is primarily piano only. Only problem is, as far as I can tell, it was played without a metronome (I suppose this left the player plenty of room to add emotion to the song).

At first I thought maybe it was just in a different time signature, which often times trips me up, so I looked up the sheet music online. Nope. It's in 4/4, for the tempo it says "78bpm Freely." Which to me means "try to play this at around 78bpm, but don't worry too much about it."

So uhh... what do I do? I thought about tediously chopping it up into smaller parts and then stretching the samples to fit, but I would probably be at the age to retire before I was able to get it done.

Any ideas? Or should I just throw in the towel and move on to something else?