If I'm not tragically mistaken, they're all still included in the game files, but simply being overridden in game by the "newer" versions. po_el_f_01 the First is still present under NWN Main Data -> data/textures02.bif -> Images, Portrait for me, anyway. If you've got them in there too, all you need to do is find and export the desired files via the NWN Explorer, rename them, toss them in your Portraits folder, and dance (this last step being the most important). :-)