Well done, I'm really glad to see you got this sorted out.
Whether it was plain old ignorance and arrogance or the person intentionally trying to rip you off, there's no excuse for this, and the fact that he tried to belittle you as collector is really weak - some people just seem like a waste of space. >:(
Do you still have the opportunity to leave feedback reflecting your experience if the item has been returned and refunded? I do hope so ;)
...and I hope this hasn't put you off of finding a Dooku if you're still after one - as Allaerra says, the majority of people on eBay are decent - I think it's always worth asking questions about any blemishes, loose parts, etc before you bid, so that in the event of the rare bad experience, you've already got something in writing from the seller you can refer back to. I've had a couple of similar experiences with camera lenses where I was refunded through Paypal and that helped.