Got my replacement Samus Figma thighs from GSC, and they have the same marks. The replacement left thigh is about the same as my current one, but the replacement right thigh is much better so I swapped it out.
Wow you got your replacements fast, that's good. One of my Samus legs is also much more noticeable than the other, even if it's not perfect I'd welcome an improvement.
I got a reply from GSC about my replacement a few days ago and they said they'd be sending them off to me soon. I'm still amazed they are sending free replacement legs overseas.