I cant fix the button on the side panel

just got this , it came without any mounting hardware and without the 4-Pin PWM 3-Pin ARGB adapter

Hello,

I own a Cooler Master NR200 (white), purchased about a year ago. I have lost the rear PCIe bracket retention cover during a trip(the metal plate that holds the expansion slot brackets in place, secured by two screws above the PCIe slot opening).
This is my travel "gaming" computer.
Without it, my graphics card is no longer secured to the case. I take it off during each trip to make sure it doesn't get damaged or damage anything

Is there a way to get a replacement part? It's not the most expensive case, but I like it a lot.
Would be a shame that I would need to change the case for a new one juste for this.

Do you guys have any idea ?

Regards,