Good price... Makes me nervous. Unless it's a HUMMER accessory dealer..I'd say back off. If there's a problem with shipping damage or quality....who's gonna back up the product.
I just bought some Aries roof rails on ebay. They were sold by "G" Style. A well know HUMMER Accessory guy under a different Ebay seller name. At least I could call him if there would have been a problem. He listed a phone number.
See if your ebay seller has a phone number listed and try calling him and see if he'll answer some of your concerns.