Double check what the last day is to make a paypal claim. A common trick is to say they're sending a replacement part and that it will take a few weeks, and by the time you realise its not coming you can't open a paypal claim. So, if it hasn't arrived by then, open the claim saying you will close it once the part arrives.
That being said, I've not had any problems with sellers on ebay from china. I had the above tactic happen to me from some guy in the USA who sent a completely incorrect part :| Seeing as how its a cheap component I'm sure it'll be replaced. If it was the whole thing (ie expensive to replace) some sellers will try to avoid refunds/replacement