A friend of mine bought a cheapo chinese copy from Ebay recently - £80 including two bars / chains, case, etc. It's 59cc, and pretty light.
What I will say though, is that it seems to run at a much lower chain speed than my Husqvarna, and though mine is only 46cc, I'd say mine has quite a bit more power too. Oh, and a few bits have fallen off his already, which is a bit scary! So, whilst I paid a fortune in comparison to get the real deal, I'm very happy that it was money well spent.
That said, Oregon are a well known maker of quality chainsaw kit. Was it actually an Oregon saw though, or just one of their bars on a cheaper saw? (come to think of it, do Oregon even sell saws? I'm not sure I've ever seen one!?).