SellerCloud can download your catalog directly off of eBay. You can have it download a specific product, or all of your active listings.
To download an individual listing go to Inventory->Add Product From eBay, but to download many listings at once follow the instructions below.
Go to Settings > Company Settings > Company Name > eBay Settings > Import eBay Products
Note: Listings must have Custom Labels before they can be downloaded. It is imperative to be sure that there are no duplicate custom labels. Otherwise, only one listing will download into SellerCloud. Furthermore, SellerCloud updates eBay listings based on the ProductID. Therefore, the duplicated listings will be updated based on the product info of the listing that downloaded into SellerCloud.
Read about downloading variation listings here.