5D MII Light Shield Plate, where to buy?

Part #: CB3-4827. It's called light shield plate according to 5D MII parts catalog manual. Anyone knows where to buy?

I forget to put it back on after I cleaned my viewfinder (a little nerves to do this), when I realized that, it's too late to find out where it is.

If anybody wants to try, here is the tutorial link: http://shimworld.wordp​ress.com …-the-5d-mk-ii-viewfinder/

In the US - Canon Parts is (732) 521-7230. Call Canon Canada and ask them?