There are a few folks that I deal with on ebay pretty often. They are both Early American Coppers (EAC) members and both know their coppers very well. I've found them to be honest and easy to deal with.
My second reason for this set of recommendations is that they have each been selling off duplicates from their collections and the ebay Large Cent market is not tracking even close to the trends pricing. As you may or may not know early this year, trends made a major price jump on Large and Half cents based mostly on the results of some large auctions that set high prices.
In dealing on ebay, I like to look for coins that have been Grellman attributed and graded. I use the Grellman net grade as an indicator of price in determining my max bids. The LC have been coming in below what I would normally consider a market price. Good time to pick up a few, even for type sets.
Grellman grades as two numbers, a technical grade and a net grade. Example 15/7+. The technical grade is 15 but the net is 7+. I'd bid 7+ money for that type of coin - unless it's something special like a RPD or Obv cud or rare variety.
early-copper - a good large cent seller
fixman11 - a good ebay large cent seller
disclaimer: this is strictly my personal opinion. I have not financial interest of any kind in the sales these gentlemen make.