$499 is definitely too high for a used WASR. I bought mine new in 2008 for $450, I think. Look around Gunbroker and check Atlantic Firearms. I've never bought anything for Atlantic, but I've heard good things about them on another forum. I'd be surprised if you find anything for $300 though. Their price on new WASR-10s is $479, but of course you'll have to add shipping and transfer fees. I just checked Gunbroker and I saw one for $440 (+ shipping and transfer fees). Seems like you could definitely get a new one for under $500.
Lastly, the quality control among WASRs is very variable. Some are pretty good, but there are definitely some lemons. Good luck.