damaged egr gasket

hi all. I drive 1.9dci scenic2005. Recently turbo went and am on replacing. My problem is I have damaged a stainless steel gasket on the egr unit(where the valve sits into the housing)when I removed it for cleaning. Thats part of the problem the other part is I dont know what the particular gasket is called to enable me to find one. Any help in identifying this part would be much appreciated. Just about to start rebuilding and need this part.

Thanks all.