I was checking the net for some 15mm orcs so I could work on an army of Oerth project. I came across Syr Hobb's Wargaming who carries East Riding Miniatures' fantasy line.
They're aren't a lot of pose variations, and they're a bit static but they do have a lot of potential. I think that they would be perfect for converting them into pig-faced orcs! I'm not sure if pig-faced orcs are specific to the world of Greyhawk, but in my mind they would fit.
Check out these pics!