Help!! Received a slightly damaged box and need help fixing it

[czar0004]

Recently I received the Black Beard figuring of ACIV and it had a tear in the transparent plastic (used at the front of the box to allow you to see the contents).

Basically I want to know what is the actual technical name of that plastic so that I can search for it on ebay so as to replace it as I hate having to look at the damaged box.

Thanks a lot for you help,
Ciskje