SRT 6.4 392

Curious to see what you guys think I can pick up a 2014 6.4 392 has a rod knock going to pop the pan off tomorrow and look deeper maybe just spun bearing or grenade it piston is my guess if I can pick this up for The cost of the core which is 750 would it be worth it for a rebuild
To put in my 73 duster
What are your thoughts