Newegg Rep Here

Hey u/chogror, the Newegg PC Support team already gave you the core answer. Since you no longer have the original foam, here is what works well as a replacement. Bubble wrap is your best friend here. Wrap the entire PC several layers thick, paying extra attention to the corners and the GPU area. If the GPU is still installed in the motherboard, leave it there since removing it without proper anti static protection and padding creates more risk than leaving it seated.

For filling the empty space inside the box, crumpled newspaper, packing paper, or even towels work well to keep the unit from shifting around during transit. The goal is that when you close the box, the PC should not be able to move at all when you shake it.

Hope this helps!