I couldn't quickly find a lot reference pictures. I don't know this character or her prop, but she looks awesome.
I think overall you've done a great job with the details. You've done pretty well with the painting. My recommendation would be to add more contrast with highlights and shadow. In your pictures some of your wonderful details get a little lost from a distance.
If I was a cosplay, a perfect cosplay, how would you know it was really me?
The Thing (1982)
(the missing word was 'imitation')