William, I assume your store banner has a URL on it? If you're talking about your Cheap Street logo (as it appears at your site) I'm pretty sure that wouldn't be a problem as long as you don't actually link it to your store. It doesn't include a URL and savvy customers will probably Google "Cheap Street Online" (if they don't just go to your ME page).
But I'm by no means an expert on this.
Another thing you can do, although it could be pretty time-consuming if you do it often, is to create a page at your site with more details about the listing's item. On that page you should include a nav bar that will take curious customers to the main part of your site -- but you can't make it obvious.
That's an idea I read about at this site: http://www.onlineauctiontrader.com/ebaylinking.htm
and there's more info about links, too.