the pushrods are the same between 5.7 and 6.4. The 5.7 springs will work, I would recomend new from the dealer as they are only about $60 set. The 6.4 spring is probably better in some way but pressures and such were almost identicle to the 5.7 and cost about $150 more for a set, they are drop on.

Timing chain is the same.

The 5.7 oil pimp is just fine, it dont have as much need for volume as a 6.4 because there are no piston squirters.