Stay cool!
I ordered 4 sets of titanium hinge-pins (3racing-ones) with a set-price of 4 us$ each (obviously a mistake, correct price is 14 us$ each). Send them the money via paypal (22,50 us$ with shipping). When they noticed the price was wrong they made me a special offer (12$ each) but i declined and asked them to re-send the money. - They did that.
I don't think they will rip you.
Regards
Robert