Did that second nut work out for you? The nuts are new but the threads on that batch were less than ideal having several failures. The new nuts have a minor redesign and excellent threads. I can send you one if you'd like.That eBay item is truly "new" then OK, but I've been through two of them and the threads were fatigued. If you buy this eBay item, then feedback later please.
I've had to order a new one unfortunately for the price. While waiting for this, my Rebel apparently runs fine with the insecurely attached nut, without 'choke' (SE) engaged.